REFERENCES
- Boydston R. (1990) Weed Science 38, 16–21.
- Frohne D. (1999) Dtsch. Apot. Ztg. 139, 4752–4754.
- Huffaker C.B., Hamai J., Nowierski R.M. (1983) Entomophaga 28(4), 387–400.
- Joshi D.D. and Uniyal R.C. (2008) J. Green Pharmacy (Juli-September), 158–161.
- Kopralev et al.. (eds,) (2002) Geography of Bulgaria. FarCom, Sofia.
- Koinov V. et al.. (1998) Atlas of soil in Bulgaria, Zemizdat, Sofiq.
- Kostova I. and Dinchev D. (2005) Phytochem. Rev. 4, 111–137.
- Koleva E. and Peneva R. (1990) Climate Book in rainfall of Bulgaria, Bulg. Acad. Sci., 6, 33–38.
- Kjuchukova M. (1983) Climate Book in air of Bulgaria, Bulg. Acad. Sci, 3, 100–113.
- Map of soils of Bulgaria M1:400 000 (1968) Institute of soil science “Nikola Pushkarov”.
- Mulinacci N., Vignoloni P., Marca G.L.a., Pieraccani G., Innocenti, M. and Vincieri F.F. (2003) Chromatographic 57, 581–592.
- Petrova A. (1979) In: Jordanov D. (ed.) Flora Reipublicae popularis, Bulgaricae, vol. VII, In aegidus Acad. Sci. Bulg., Serdicae, 78–79.
- Savchev P. and Stoyanov N. (1972) Trudove NICHPHI, 8, 201–211.
- Stojanov N., Stefanov B. and Kitanov, B. (1967). Flora Bulgarica II, Nauka I Izkustvo, Sofia.
- Shreter A., Krilova I., Borisova N., Kuriovich L. and Bocharov I. (1986) USSR State Committee of Forestry Enterprise, Moscow.
- Tomova M., Gyulemetova R., Zarkova S., Peeva S., Pangarova T. and Simova, M. (1981) First Intern. Conf. Chem., Biotechnol. Biol. Active Nat. Prod., Proceedings, Varna, September 3, 289–291.
- Toshev A. (1895) Periodical journal, 49–50, 329–356.
- Toshev A. (1902) Periodical journal, 62, 33.
- Tutin T.G. (1968) In: Tutin, T.G., Heywood, V.N., Burges, N.A., Moole, D.M., Valentine, D.H., Walters, S.M., Webb, D.A., Eds.) Flora Europaea. Cambridge University Press Cambridge, p. 205.
- Urumov I. (1906) VI Contribute to Bulgarian Flora, 22, 27 p.
- Urumov I. (1908) IX Contribute to Bulgarian Flora, 22, p. 17
- Urumov I. (1917) XII Contribute to Bulgarian Flora, 7, p. 58
- Urumov, I (1929) Omnibus Bulg. Acad. Sci., 25, 6–13.
- Velenovski Y. (1891) Flora Bulgarica, p. 115.