A First-Rate Scholar and Man of Many Parts Ian David Lewis Michael (1936–2020)

Ian Michael, who died in Madrid on 24 July 2020, aged eighty-four after a long illness, made a deep impression on the world of Hispanic Studies and on all who came across him professionally or personally.

In common with several other notable Hispanists, Ian hailed from Neath in South Wales, though the Michael family originally came from Antwerp, fleeing to Wales in the sixteenth century to escape Spanish persecution. His father was Cyril G. Michael and his mother was Glynis Michael (née Lewis). The former played rugby and the latter tennis and Ian himself was a promising school-boy rugby player until injury curtailed his playing days. The sports field’s loss was Hispanism’s gain. Ian began to study Spanish at age thirteen; this, he liked to remember, was to avoid taking physics. He progressed from Neath Grammar School for Boys, to read French and Spanish (he preferred Spanish) at King’s College London where he took a first in 1957. Years later, in 2001, he would become a Fellow of KCL, an honour he specially valued. Among those who taught him and fourteen other students doing Honours at Kings, and who turned him into a Hispanist, were Rafael Martínez Nadal, friend and scholar of Lorca, and Rita Hamilton, who was responsible for developing the Medieval Literature course there and trained quite a number of students like Ian who went on to become eminent Medievalists in their own right. The undergraduates Ian studied with became a close-knit group of friends who met up regularly for decades afterwards.¹ Ian’s enduring debt to Rita Hamilton is clear from the memoir he wrote for the Bulletin in 1983, in which he recalls how ‘she inspired many of her students with a desire to do research at an early age in their academic career’, and that ‘she had the art of a great teacher: to give the pupil the impression of making important discoveries, and to leave the subject open-ended, with much still to be pursued’.² Ian went on to acquire that same art in large measure.

It was while still an undergraduate that Ian got to know Spain at first hand, when, as part of his course at KCL, he was sent in 1955 to spend several months in Madrid and Seville, during which he acquired his enduring fondness for attending bullfights, something he enjoyed, so he said, ‘como un espectáculo y como un arte, sin pensar lo que pasa con los toros’.³ The photograph of Ian, which he chose himself for inclusion in his Festschrift (2004) shows him standing against the background of a bullring. When Queen Sofía was presented with a bound copy of his Festschrift she looked at the photo and asked him if it had been taken in a tennis court. She laughed when Ian told her that ‘it was taken in 1988 in a small bullring in the Sierra de Madrid owned by Antoñita Linares, though the caption flatteringly claimed to be from 2002’.⁴

From King’s, in the same year he graduated, Ian went to take up a post at the University of Manchester where he undertook research for his thesis on ‘The Treatment of Classical Themes in the Libro de Alexandre’ (PhD 1967), supervised by J. W. Rees, another scholar he greatly admired. At Manchester University he counted among his colleagues in the Department of Hispanic Studies, Herbert Ramsden, Gerald Gybbon-Monypenny, Margaret Wilson, Giovanni Pontiero, Victor Dixon, Margaret Raventós and Derek Gagen. Ian enjoyed the Manchester Medieval Society, with its lively debates, in which Rees, too, was very active, and there were many opportunities, inside and outside the Society, for debating ‘the burning questions of the day concerning methods of textual editing, the structure of epic and romance, and orality vs literacy’.⁵

From Manchester, Ian moved to Southampton University, taking up the Chair of Spanish in 1971 on the departure of Nigel Glendinning. While at Southampton he managed, typically, to be an effective head of department while producing a steady stream of influential publications and studying for an undergraduate degree in Portuguese.

Ian moved to Oxford in 1982 when Sir Peter Russell retired, to take up the King Alfonso XIII Professorship of Spanish Studies, the post he held with distinction until his own retirement in 2003. Ian’s tenure at Oxford coincided with the (at first gradual) expansion of Spanish as an undergraduate subject there and in the United Kingdom as a whole, and Ian was able to influence this trend both within the Faculty of Medieval and Modern Languages and, perhaps most spectacularly, at Exeter College where he held his Professorial Fellowship. Ian’s contacts and energy led to the creation of the Queen Sofía Fellowship in Modern Spanish Literature, which was held by a succession of talented early-career scholars. The association of Exeter College with Spanish Studies underpinned two visits to Oxford by Queen Sofía as well as that made by the present King and Queen of Spain in July 2017, during the tenure of Ian’s successor, Edwin Williamson.

Ian was a sharp and able administrator, aware of the bigger picture but with a love for details and an enviable ability to recall them. He enjoyed remembering that on arriving in Oxford in October 1982 he found an unspent balance of £24,000 in the Spanish Fund which had accumulated since Peter Russell’s retirement: ‘When I proposed […] we purchase one desktop PC and six of the new IBM portable PCs with printers which the graduate students in the sub-faculty could borrow to word-process their theses, I met stiff opposition at faculty level, where there was then not even an electric typewriter […]. Peter not only intervened behind the scenes to help me get my way but became an enthusiastic learner of the new technology, taking up electronic mail and internet searches as soon as they became available’.⁶

He served Hispanism in the UK and Ireland as President of the AHGBI between 1990 and 1992, the year in which the Association held its annual conference at Huelva, to commemorate splendidly the 500^th anniversary of Columbus’ voyage of discovery to the ‘New World’. He had been a member of the AHGBI Committee as early as 1963. He was a Corresponding Member of the Royal Spanish Academy and had become a Commander of the Order of Isabel la Católica in 1986.

He was also a long-serving member of the Bulletin of Spanish Studies’ Editorial Advisory Committee (which he had joined in 1983), as well as a guest editor and contributor. Ian edited and contributed to two outstanding Special Numbers of the Bulletin on very different topics. One of them, co-edited with David Pattison, contained the proceedings of Context, Meaning and Reception of ‘Celestina’. A Fifth Centenary Symposium that had been held at the Taylor Institution and St Peter’s College, Oxford in October 1999, to which most of the UK’s leading scholars of the work contributed, including Peter Russell on ‘The Celestina Then and Now’, and Ian himself on ‘Celestina and the Great Pox’.⁷ The other Bulletin Special Number, co-edited with Robin Fiddian, was Sound on Vision. Studies on Spanish Cinema, the product of the ‘Spanish Film Event’ held in Oxford in 1997 and 1998.⁸ The involvement of Ian, a dedicated Medievalist, in this project might seem strange to some. But, as he liked to remind us, and as he put it to Juan Cruz in the interview he gave for El País in 2007: ‘yo fui responsable de que en Oxford se introdujera el cine como objeto de estudio. Solo hasta finales del siglo XX lo consideraron allí digno de interés’.

These two Special Issues, important though they are, represent only a small part of the contributions made by Ian Michael for decades to the work and reputation of the Bulletin. He was frequently asked to peer-assess articles on all manner of medieval and early modern topics, in the years when such articles were still being submitted to the journal in large numbers. He rarely refused such requests, no matter how busy he was; but, when he did so, always with a sincere apology, he took the trouble to suggest the names of several highly suitable alternative readers. Even after he retired and moved to Spain, he kept regularly in touch with the Bulletin’s editors, who usually heard first through an email from Ian of the death of eminent Hispanists, and in the same email there would be helpfully included some names of people who might be relied upon to write informative and balanced memoirs. In 2005–2006, a period in which several internationally known Hispanists died (including Robert Pring-Mill, Alonso Zamora Vicente, Ivy McClelland and Peter Russell), he emailed the Editors saying ‘everyone is dying except us!’ He was at first reluctant to write Peter Russell’s memoir and offered the Editors the names of other potential authors, fearing that he would not do him justice (he need not have worried!). He wrote: ‘Can I think about it? It might be best done by one of his former pupils, such as Ron Truman, or Clive Griffin or Bruce Taylor who is in LA. On the other hand, I’d have the opportunity to do for him what he did for me in the BSS in December 2004’. He agreed in the end, saying: ‘Yes, I will do the memoir of PER for you (I’ve turned down The Independent and The Daily Telegraph, not only on ideological grounds! I hate doing things hastily)’. He ended the email ‘Yours lugubriously, Ian’. He sent in a masterly evaluation attached to an email in which he said: ‘At last I have managed to complete the memoir of Peter Russell, which has taken a lot of research and consultation. It contains c.5,000 words … This is much longer than you normally permit for a Memoir (though in the past there were long memoirs of other Hispanists who worked for the Govt in secret, such as Rica Brown and Helen Grant). Don’t hesitate to let me know if you want to cut it down’.⁹ The Editors published Ian’s memoir in full.¹⁰ The debt owed by the Bulletin and its Editors to Ian Michael down the decades meant that when they were approached by Colin Thompson to ask, on behalf of Ian’s Oxford colleagues, whether the Bulletin would consider issuing a Number in his honour, there came the immediate agreement to publish a Festschrift which, at Ian’s request, focused on The Iberian Book and its Readers. Essays for Ian Michael. Peter Russell opened the volume with ‘Ian Michael: A Personal Appreciation’.¹¹

Ian Michael’s scholarly interests were primarily in the field of medieval literature. Coming from an undergraduate course at KCL in the time of Rita Hamilton to a PhD at the Manchester of J. W. Rees, it is unsurprising that this traditional philological background forms an important if not indeed paramount element in his published scholarship. His edition of the Poema de Mio Cid (Castalia, 1976, 2^nd ed. 1978 with various later reprints), for example, is much more interventionist textually and linguistically than the edition by Colin Smith (Oxford: Clarendon 1972; Spanish-language successor: Cátedra, 1976). It may be recorded anecdotally that L. P. Harvey (himself a traditional philologist) was happier with Michael’s text than Smith’s. In a ‘brief notice’ he did about Ian’s second Castalia (1978) edition of the PMC, Harvey concluded: ‘We must all be delighted to see that an edition which at an earlier stage seemed likely to be one of the casualties of the economic crisis of the early seventies should be enjoying such well-deserved success’.¹² But linguistic history was not the limit of Ian’s scholarly armoury; the breadth of vision in The Treatment of Classical Material in the ‘Libro de Alexandre’ (the book of his PhD thesis, Manchester University Press, 1970) would suffice as testimony of this, while the historical and geographical dimensions of the annotation to his Castalia edition of the Poema de Mio Cid are much more ample than the notes to the edition by Colin Smith: a difference of focus which should have given Michael’s edition an advantage in the hands of undergraduates even if manuscript purists may have preferred to quote from Smith’s more conservative treatment of the text. This reflects Ian’s detailed study, partly on the ground, of the routes described in the poem, published in articles in 1976–1977, as well as in the notes to the edition. Ian vividly recalled undertaking ‘an exploration of the Cidian routes’ with Rita Hamilton, Alan Deyermond and Harvey Sharrer in 1971, during which Rita ‘would stand entranced at important sites reading aloud from a battered copy of the Poema, while her harassed companions pored over inadequate maps’.¹³ Other articles on the poem followed up to 2002, in which he dealt with different and wider questions as well as with points of detail.

Ian also knew a lot about sixteenth-century book-printing in Spain, as Clive Griffin discovered when he examined his doctoral thesis, and he came to appreciate the relevance of the history of the book to his field of study. He became, in Pedro Cátedra’s words, a ‘denodado investigador de bibliotecas reales y principescas de la Edad Media y grandes colecciones nobiliarias de la Edad Moderna’.¹⁴ Ian himself said: ‘La verdad es que una de las grandes preocupaciones de mi vida han sido las bibliotecas, cómo se han formado, cómo se han cuidado, y eso me llevó a ampliar mis intereses’.¹⁵ Articles followed on a range of aspects of that area of scholarship which included contributions to the history of libraries and collecting (in which may be included his spirited defence of the cataloguing by librarians at the Biblioteca de Palacio in his contribution to the lively debate on the history and significance of the then recently-edited ‘Celestina de Palacio’ manuscript).¹⁶ This article reflects another facet of Ian’s medievalism: an intense loyalty, seen perhaps most clearly in his Manchester edition (1975) of the Poema de Mio Cid, deprived of the dense annotation which was to be his editorial hallmark with Castalia, but published to accompany the translation by Rita Hamilton and Janet Perry. That this venerable version had been based on the edition by Ramón Menéndez Pidal created some unfortunate mismatches between the ‘parallel’ texts; but one suspects that the principal concern for Ian was to see the Hamilton/Perry translation through to publication despite the problems encountered. David Pattison, who reviewed this book for the Bulletin, found Ian’s introduction to be ‘lucid, fair-minded and full of good sense about such matters as historicity, metre, poetic language and structure’, and that Ian had written ‘perceptively and persuasively of the poetic qualities of the work as an exemplary work of art with a carefully planned structure’.¹⁷

Ian’s final edition of the Poema de Mio Cid was completed, after his retirement, in collaboration with Juan Carlos Bayo whom Ian regarded as ‘an outstanding textual critic and editor, and a beaver in the archives’. In reviewing this re-edition, which came out in 2008, Irene Zaderenko begins by acknowledging that ‘[e]n las últimas décadas del siglo pasado, las ediciones de Colin Smith (1972) e Ian Michael (1976) aportaron una renovación total del texto y de las aproximaciones críticas al Cantar (o Poema) de Mio Cid’. She goes on to say, nevertheless, that this new edition supplies ‘novedades significativas y, lo que es más importante, bien meditadas’; and she concludes: ‘Esta nueva edición del CMC será de gran utilidad tanto para estudiantes que se inician en los estudios cidianos como para profesores interesados en nuevas aproximaciones críticas al texto’.¹⁸ The edition of Berceo’s Milagros de Nuestra Señora on which Ian had been working for at least twenty years had appeared in 2006, also published by Castalia and co-edited with Juan Carlos Bayo, who had been contracted in Oxford to assist Ian with its completion. The younger scholar put so much work into enriching (Ian’s word) the Introduction and revising the text, a collation of three manuscripts, that at Ian’s insistence ‘the publisher put his name before mine on the cover of the edition’. It pleased Ian greatly that the published edition ‘happened to come out with 500-numbered pages (plus the 14 plates; pity there wasn’t one more), because … the number 5 and its multiples represent the Virgin M-A-R-I-A in numerology; it is quite a miracle that this has come about’.¹⁹ One of many Medievalists to welcome this edition, Geraldine Coates finds in it ‘stimulating new perspectives upon Berceo’s creative talent and the vibrant linguistic context in which he was writing’, and approves the ample Introduction which reinstated Berceo’s ‘solid theological background, the universal thrust of his collection, and his masterly union of doctrine and poetry […] [T]his is a thorough, reliable, and learned edition of a precious text. It successfully captures the author’s delight in the nuances, patterns and vicissitudes of language, and the invigorating effects of his literary talents upon the rich tradition of Marian worship.’²⁰

From his scholarly works, the reader swiftly appreciates Ian’s overarching command of his subject—whether historical or literary—as well as his aforementioned eye for detail. There is perhaps no better example than his investigation, published in 2001 in a Festschrift for Ron Truman, of how Don Quixote came to Oxford. (The answer: partly in a barrel on a barge.) What tends only to be glimpsed on paper is his mischievousness and sense of fun, which were more quickly appreciated in personal meetings. The offprint he gave to Jonathan Thacker of that study, bound in a reproduction of the title page of the first edition of Cervantes’s novel, was, he claimed in his dedication of it, ‘reduced to the exact size of the princeps of the Quixote’.²¹

Ian was a writer of fiction himself, publishing as ‘David Serafín’ (a pseudonym combining ‘David’, one of his middle names, with an indirect reference to ‘Michael’) a series of crime novels featuring the detective Bernal, who operated in the Madrid of the Transition, of which Ian had first-hand experience. For the first of these, Saturday of Glory, he won the Crime Writers Association’s John Creasey prize in 1979. Bernal’s cases came close to screen adaptation.²² And Ian was a fictional character too, the raw material for Aidan Kavanagh, who featured in Javier Marías’ Oxford-based novel, Todas las almas, as well as appearing as himself in the follow-up, Negra espalda del tiempo: ‘Ian Michael, de Exeter College, que visita Madrid con frecuencia llevado por sus pesquisas de medievalista, su debilidad por la grey taurina, sus investigaciones histórico-callejeras para las novelas policiacas que escribe con un angelical pseudónimo y su temeraria curiosidad o gusto por los bajos fondos y los aspirantes a hampones’.²³ Marías himself drew attention both to Ian’s immediate acceptance that the novel was not a roman à clef and his simultaneous tendency to refer to his colleagues by their invented names in correspondence.

Jonathan Thacker’s initial impressions of Ian, whom he first met in the bar at the Association of Hispanists Conference at Canterbury, were confirmed when he became his colleague in Oxford for two years in 2001. He was kind and loyal, generous to a fault, an excellent raconteur, mischievous and something of a hypochondriac, encouraging to research students and early-career academics, giving them time even when he was not their supervisor or mentor, agudo, ingenioso and prudente. Others—former students and colleagues—have stressed to us Ian’s commitment to his students, his generosity towards them even after graduation, and his dedication to his mother.

After his retirement in 2003, Ian moved to Madrid, where he lived close to the Biblioteca Nacional and spent time in the company of his many friends and acquaintances. He continued to exert an important influence in Spain, a country he had first visited in 1955, and particularly Madrid, where he had been the first Visiting Professor at the Complutense.²⁴ His long-term partner, David Bernal, whom he had known for decades and married in Madrid, passed away four months after Ian, on 26 November 2020.

‘Siempre me he sentido un poco español, desde los años setenta. Cada vez más. Prefería estar aquí que allí’, said Ian, in the interview he gave in Madrid in 2007. None the less, he concluded the same interview by saying:

Pero Oxford es un sitio maravilloso para hacerse; en ningún lugar del mundo hay tanto debate, tanto intercambio de opiniones entre facultades […] En un colegio típico de Oxford puede haber 25 o 30 personas, cada una de una asignatura distinta, así que en las cenas y en los almuerzos salta al menos una idea por asignatura.²⁵

To mark his retirement Ian threw a splendid dinner at Exeter College, of which colleagues and friends who attended, many from outside Oxford and among them quite a few non-academics (one was Colin Dexter, the creator of Inspector Morse), still have good memories. After his move to Spain, Ian returned often to Oxford where, for many relaxed lunches and some more formal events, he met up with friends and colleagues among whom was Peter Russell until ‘Death … took him peacefully away’ aged ninety-two.²⁶ Since he knew Ian better than most of us, perhaps there is no better way to end this memoir than to repeat what Peter said on the record about his successor in the King Alfonso XIII Professorship of Spanish Studies:

What [Ian] is above all is a first-rate scholar, a successful professor, a good companion, and a man of unusually many parts who manages to bring an air of drama even to the more unpromising routines of academe.²⁷

Notes

1 Details of Ian’s early life are mainly taken from his own recollections as recorded in the interview he did with Juan Cruz, aptly titled ‘El profesor risueño’, published in El País, 14 de enero de 2007, <https://elpais.com/diario/2007/01/14/eps/1168759607_850215.html> (accessed 18 March 2021).

2 Ian Michael, ‘Rita Hamilton (1907–1982)’, BHS, LX:2 (1983), 135–36 (p. 135). In his review of Medieval Hispanic Studies Presented to Rita Hamilton, ed. A. D. Deyermond (London: Tamesis, 1976), BHS, LVI:1 (1979), 54–56, a volume to which Ian naturally contributed an article, on the Poema de Mio Cid, Fred Hodcroft described Rita Hamilton as ‘one of the most influential Hispanists of her generation’ (56).

3 Ian Michael, in his interview with Juan Cruz, El País, 14.1.2007.

4 An anecdote Ian recounted in an email sent to one of the Bulletin’s General Editors (Ann Mackenzie), 9 May 2005.

5 Ian Michael, ‘Gerald Burney Gybbon-Monypenny (1923–2002), BSS, LXXX:1 (2003), 103–06 (p. 104).

6 Recounted in Ian Michael, ‘Sir Peter Russell (1913–2006)’, BSS, LXXXIII:8 (2006), 1133–44 (p. 1142).

7 See Context, Meaning and Reception of ‘Celestina’. A Fifth Centenary Symposium, ed. Ian Michael & David G. Pattison, BHS (Glasgow), LXXVIII:1 (2001). For the articles by Peter Russell and Ian Michael respectively, see pp. 1–11 and 103–38.

8 See Sound on Vision. Studies on Spanish Cinema, ed. Robin Fiddian & Ian Michael, BHS (Glasgow), LXXVI:1 (1999).

9 The extracts quoted are taken from emails by Ian Michael to Ann Mackenzie, dated 28 & 30 June 2006 & 22 August 2006.

10 Michael, ‘Sir Peter Russell (1913–2006)’.

11 See Peter Russell, ‘Ian Michael: A Personal Appreciation’, in The Iberian Book and its Readers. Essays for Ian Michael, ed. Nigel Griffin, Clive Griffin & Eric Southworth, BSS, LXXXI:7–8 (2004), vii–x.

12 See L. P. Harvey’s ‘Brief Notice’ of the Poema de Mio Cid, ed. Ian Michael, 2ª ed. (Madrid: Castalia, 1978), BHS, LVII:3 (1980), 266–67.

13 Michael, ‘Rita Hamilton (1907–1982)’, 136.

14 Pedro M. Cátedra, ‘La biblioteca de la Universidad de Toledo (siglo XVI)’, in The Iberian Book and its Readers. Essays for Ian Michael, ed. Griffin, Griffin & Southworth, 927–56 (p. 927).

15 Quoted from Ian Michael’s interview with Juan Cruz, El País, 14.1.2007.

16 See Ian Michael, ‘La Celestina de Palacio: el redescubrimiento del Ms. II-1520 (sign. ant. 2.A.4) y su procedencia segoviana’, Revista de Literatura Medieval, III (1991), 149–61.

17 See David Pattison’s review of The Poem of the Cid, edited by Ian Michael. Prose translation by Rita Hamilton & Janet Perry (Manchester: Manchester U. P./New York: Barnes & Noble, 1975), BHS, LIV:2 (1977), 146–48 (p. 147).

18 Irene Zaderenko, review of Cantar de Mio Cid, edición de Juan Carlos Bayo & Ian Michael (Madrid: Castalia, 2008), BSS, LXXXVII:6 (2010), 849–50.

19 References to his editions of the Poema and the Milagros co-edited with Dr Bayo are taken from emails sent by Ian Michael to Ann Mackenzie on 16 April and 25 September 2006, and from a letter by Ian shared with her, dated 3 February 2006.

20 Geraldine Coates, review of Gonzalo de Berceo, Milagros de Nuestra Señora, edición de Juan Carlos Bayo & Ian Michael (Madrid: Castalia, 2006), BSS, LXXXV:3 (2008), 353–54.

21 See Ian Michael, ‘How Don Quixote Came to Oxford: The Two Bodleian Copies of Don Quixote, Part I (Madrid: Juan de la Cuesta, 1605)’, in Culture and Society in Habsburg Spain: Studies Presented to R. W. Truman by His Pupils and Colleagues on the Occasion of His Retirement, ed. Nigel Griffin, Clive Griffin, Eric Southworth & Colin Thompson (London: Tamesis, 2001), 95–120. For this and other publications by Ian Michael, see ‘The Publications of Ian Michael’, in The Iberian Book and its Readers. Essays for Ian Michael, ed. Griffin, Griffin & Southworth, xiii–xx.

22 For more details of his published detective novels, see ‘The Publications of Ian Michael’, Section I ‘Writing as David Serafín: Novels’, in The Iberian Book and its Readers. Essays for Ian Michael, ed. Griffin, Griffin & Southworth, xix–xx. In an email to Ann Mackenzie, dated 17 January 2006, Ian mentions that he had signed an option with Spanish television for a series: ‘I’m still waiting to see if the producer of RTVE is going ahead to turn my six published novels plus three more outline drafts which I have completed into a TV series’. It appears that Ian never did elaborate these three ‘outline drafts’ into further published novels of detective fiction.

23 Javier Marías, Negra espalda del tiempo (n.p.: Punto de Lectura, 2000), 37.

24 For evidence of the high regard in which Ian was held in Spain, both before and after he moved there to live, see María Luisa López-Vidriero, ‘Un reino sin un duque: Ian Michael y la Real Biblioteca’, Avisos/Noticias de la Real Biblioteca, XXVI:91 (mayo–agosto, 2020), 9–10.

25 Ian Michael, interviewed by Juan Cruz, in ‘El profesor risueño’, El País, 14.1.2007.

26 Michael, ‘Sir Peter Russell (1913–2006)’, 1144.

27 Russell, ‘Ian Michael: A Personal Appreciation’, x.

In this memoir, as well as to Sir Peter’s reminiscences and observations, we are indebted to a number of individuals who have helped by providing information about Ian: Clive Griffin and Eric Southworth; David Hook, who provided insights and comments we have drawn on in the paragraphs concerning Ian’s medieval scholarship; John Jenkins, retired librarian at the University of Aberystwyth, who corrected a mistake made about Ian’s father in the obituary Jonathan Thacker published in The Guardian; and Phillip Humphries, a former student of Ian’s at Southampton University.

* Disclosure Statement: No potential conflict of interest was reported by the authors.