Effects of perceived service quality, website quality, and reputation on purchase intention: The mediating and moderating roles of trust and perceived risk in online shopping

References

• Agag, G. M., & El-Masry, A. A. (2017). Why do consumers trust online travel websites? Drivers and outcomes of consumer trust toward online travel websites. Journal of Travel Research, 56(3), 347–20. https://doi.org/https://doi.org/10.1177/0047287516643185
   Google Scholar
• Ahmad, S. Z., Abu Bakar, A. R., & Ahmad, N. (2019). Social media adoption and its impact on firm performance: The case of the UAE. International Journal of Entrepreneurial Behavior & Research, 25(1), 84–111. https://doi.org/https://doi.org/10.1108/IJEBR-08-2017-0299
   Google Scholar
• Al-dweeri, R. M., Ruiz Moreno, A., Montes, F. J. L., Obeidat, Z. M., & Al-dwairi, K. M. (2019). The effect of e-service quality on Jordanian student’s e-loyalty: An empirical study in online retailing. Industrial Management & Data Systems, 119(4), 902–923. https://doi.org/https://doi.org/10.1108/IMDS-12-2017-0598
   Google Scholar
• Almousa, M. (2011). Perceived risk in apparel online shopping: A multi dimensional perspective. Canadian Social Science, 7(2), 23–31. https://doi.org/http://dx.doi.org/10.3968/j.css.1923669720110702.003
   Google Scholar
• Ariff, M. S. M., Sylvester, M., Zakuan, N., Ismail, K., & Ali, K. M. (2014). Consumer perceived risk, attitude and online shopping behaviour; empirical evidence from Malaysia [ Paper presentation] IOP Conference Series: Materials Science and Engineering, Jakarta, Indonesia.
   Google Scholar
• Armstrong, J. S., & Overton, T. S. (1977). Estimating nonresponse bias in mail surveys. Journal of Marketing Research, 14(3), 396–402. https://doi.org/https://doi.org/10.1177/002224377701400320
   Google Scholar
• Arnott, D. C., Wilson, D., Mukherjee, A., & Nath, P. (2007). Role of electronic trust in online retailing. European Journal of Marketing, 41(9/10), 1173–1202. https://doi.org/https://doi.org/10.1108/03090560710773390
   Google Scholar
• Badwan, J. J., Al Shobaki, M. J., Naser, S. S. A., & Amuna, Y. M. A. (2017). Adopting technology for customer relationship management in higher educational institutions. International Journal of Engineering and Information Systems, 1(1), 20–28. http://dstore.alazhar.edu.ps/xmlui/handle/123456789/364
   Google Scholar
• Bagozzi, R. P., & Yi, Y. (1988). On the evaluation of structural equation models. Journal of the Academy of Marketing Science, 16(1), 74–94. https://doi.org/https://doi.org/10.1007/BF02723327
   Google Scholar
• Barclay, D., Higgins, C., & Thompson, R. (1995). The partial least squares (PLS) approach to casual modeling: Personal computer adoption and use as an Illustration. Technology Studies, 2(2), 285–309.
   Google Scholar
• Bauman, A., & Bachmann, R. (2017). Online consumer trust: Trends in research. Journal of Technology Management & Innovation, 12(2), 68–79. https://doi.org/https://doi.org/10.4067/S0718-27242017000200008
   Google Scholar
• Becker, S., Bryman, A., & Ferguson, H. (2012). Understanding research for social policy and social work: Themes, methods and approaches. Policy Press.
   Google Scholar
• Belanche, D., Casaló, L. V., & Guinalíu, M. (2012). Website usability, consumer satisfaction and the intention to use a website: The moderating effect of perceived risk. Journal of Retailing and Consumer Services, 19(1), 124–132. https://doi.org/https://doi.org/10.1016/j.jretconser.2011.11.001
   Google Scholar
• Carlson, J., Wyllie, J., Rahman, M. M., & Voola, R. (2019). Enhancing brand relationship performance through customer participation and value creation in social media brand communities. Journal of Retailing and Consumer Services, 50, 333–341. https://doi.org/https://doi.org/10.1016/j.jretconser.2018.07.008
   Google Scholar
• Carlson, J. R., & Kukar-Kinney, M. (2018). Investigating discounting of discounts in an online context: The mediating effect of discount credibility and moderating effect of online daily deal promotions. Journal of Retailing and Consumer Services, 41, 153–160. https://doi.org/https://doi.org/10.1016/j.jretconser.2017.12.006
   Google Scholar
• Çetinkaya, F., & Karabulut, N. (2016). Validity and reliability of the Turkish version of the Visual Analog Sleep Scale. Kontakt, 18(2), e84–e89. https://doi.org/https://doi.org/10.1016/j.kontakt.2016.05.003
   Google Scholar
• Chang, M. K., Cheung, W., & Tang, M. (2013). Building trust online: Interactions among trust building mechanisms. Information & Management, 50(7), 439–445. https://doi.org/https://doi.org/10.1016/j.im.2013.06.003
   Google Scholar
• Chen, X., Huang, Q., & Davison, R. M. (2017). The role of website quality and social capital in building buyers’ loyalty. International Journal of Information Management, 37(1), 1563–1574. https://doi.org/https://doi.org/10.1016/j.ijinfomgt.2016.07.005
   Google Scholar
• Chen, Y.-S., & Huang, S. Y. (2017). The effect of task-technology fit on purchase intention: The moderating role of perceived risks. Journal of Risk Research, 20(11), 1418–1438. https://doi.org/https://doi.org/10.1080/13669877.2016.1165281
   Google Scholar
• Chin, W. W. (2010). How to write up and report PLS analyses. In E. V. Vinzi., W. W. Chin, J. Henseler, & H. Wang (Eds.), Handbook of Partial Least Squares (pp. 655–690). Springer.
   Google Scholar
• Chin, W. W., Marcolin, B. L., & Newsted, P. R. (2003). A partial least squares latent variable modeling approach for measuring interaction effects: Results from a Monte Carlo simulation study and an electronic-mail emotion/adoption study. Information Systems Research, 14(2), 189217. https://doi.org/https://doi.org/10.1287/isre.14.2.189.16018
   Google Scholar
• Chiu, C.-M., Wang, E. T., Fang, Y.-H., & Huang, H.-Y. (2014). Understanding customers‘ repeat purchase intentions in B2C e-commerce: The roles of utilitarian value, hedonic value and perceived risk. Information Systems Journal, 24(1), 85–114. https://doi.org/https://doi.org/10.1111/j.1365-2575.2012.00407.x
   Google Scholar
• Chuang, H.-M., & Fan, C.-J. (2011). The mediating role of trust in the relationship between e-retailer quality and customer intention of online shopping. African Journal of Business Management, 5(22), 9522–9529. https://doi.org/https://doi.org/10.5897/AJBM.9000613
   Google Scholar
• Clement, J. (2019). E-commerce worldwide – statistics & facts. https://www.statista.com/topics/871/online-shopping/
   Google Scholar
• Cohen, J. (1998). Statistical Power Analysis for the Behavioural Sciences. Lawrence Erlbaum Associates.
   Google Scholar
• Das, G. (2016). Antecedents and consequences of trust: An e-tail branding perspective. International Journal of Retail & Distribution Management, 44(7), 713–730. https://doi.org/https://doi.org/10.1108/IJRDM-06-2015-0089
   Google Scholar
• Di Fatta, D., Musotto, R., & Vesperi, W. (2016). Analyzing E-commerce websites: A quali-quantitive approach for the User Perceived Web Quality (UPWQ). International Journal of Marketing Studies, 8(6), 33–44. https://doi.org/https://doi.org/10.5539/ijms.v8n6p33
   Google Scholar
• Dillman, D. A. (2006). Why choice of survey mode makes a difference. Public Health Reports, 121(1), 11–13. https://doi.org/https://doi.org/10.1177/003335490612100106
   Google Scholar
• Doney, P. M., & Cannon, J. P. (1997). An examination of the nature of trust in buyer–seller relationships. Journal of Marketing, 61(2), 35–51. https://doi.org/https://doi.org/10.1177/002224299706100203
   Google Scholar
• Dutot, V., & Bergeron, F. (2016). From strategic orientation to social media orientation: Improving SMEs’ performance on social media. Journal of Small Business and Enterprise Development, 23(4), 1165–1190. https://doi.org/https://doi.org/10.1108/JSBED-11-2015-0160
   Google Scholar
• Escobar-Rodríguez, T., & Bonsón-Fernández, R. (2017). Analysing online purchase intention in Spain: Fashion e-commerce. Information Systems and e-Business Management, 15(3), 599–622. https://doi.org/https://doi.org/10.1007/s10257-016-0319-6
   Google Scholar
• Fedorko, R., Bacik, R., & Kerulova, V. (2017). The analysis on the importance of the reputation management in relation to e-commerce subjects. Polish Journal of Management Studies, 15(1), 48–56. https://doi.org/https://doi.org/10.17512/pjms.2017.15.1.05
   Google Scholar
• Fornell, C., & Larcker, D. F. (1981). Evaluating structural equation models with unobservable variables and measurement error. Journal of Marketing Research, 18(1), 39–50. https://doi.org/https://doi.org/10.1177/002224378101800104
   Google Scholar
• Hair, J. F., Black, W. C., Babin, B. J., & Anderson, R. E. (2010). Multivariate Data Analysis: Global Edition. Upper Saddle River, NJ.
   Google Scholar
• Hair, J. F., Ringle, C. M., & Sarstedt, M. (2011). PLS-SEM: Indeed a silver bullet. Journal of Marketing Theory and Practice, 19(2), 139–152. https://doi.org/https://doi.org/10.2753/MTP1069-6679190202
   Google Scholar
• Hair, J. F., Sarstedt, M., Ringle, C. M., & Mena, J. A. (2012). An assessment of the use of partial least squares structural equation modeling in marketing research. Journal of the Academy of Marketing Science, 40(3), 414–433. https://doi.org/https://doi.org/10.1007/s11747-011-0261-6
   Google Scholar
• Hair Jr, J. F., Hult, G. T. M., Ringle, C., & Sarstedt, M. (2016). A Primer on Partial Least Squares Structural Equation Modeling (PLS-SEM). Thousand Oaks, CA.
   Google Scholar
• Henseler, J., Ringle, C. M., & Sinkovics, R. R. (2009). The use of partial least squares path modeling in international marketing. In R. Sinkovics & P. Ghauri (Eds.), New Challenges to International Marketing (pp. 277–319). Emerald Group Publishing Limited.
   Google Scholar
• Hong, I. B., & Cha, H. S. (2013). The mediating role of consumer trust in an online merchant in predicting purchase intention. International Journal of Information Management, 33(6), 927–939. https://doi.org/https://doi.org/10.1016/j.ijinfomgt.2013.08.007
   Google Scholar
• Hsu, C.-L., Chen, M.-C., & Kumar, V. (2018). How social shopping retains customers? Capturing the essence of website quality and relationship quality. Total Quality Management & Business Excellence, 29(1–2), 161–184. https://doi.org/https://doi.org/10.1080/14783363.2016.1171706
   Google Scholar
• Ibrahim, A. M. M., Hassan, M. S. H., & Yusuf, S. (2019). Factors determining e-shopping compliance by Nigerians. In M. Khosrow-Pour (Ed.), Advanced methodologies and technologies in digital marketing and entrepreneurship (pp. 219–232). IGI Global.
   Google Scholar
• Internet World Stats (2019). World internet usage and population statistics, 2019 mid-year estimates. https://internetworldstats.com/stats.htm
   Google Scholar
• Jeon, H., Jang, J., & Barrett, E. B. (2017). Linking website interactivity to consumer behavioral intention in an online travel community: The mediating role of utilitarian value and online trust. Journal of Quality Assurance in Hospitality & Tourism, 18(2), 125–148. https://doi.org/https://doi.org/10.1080/1528008X.2016.1169473
   Google Scholar
• Kamalul Ariffin, S., Mohan, T., & Goh, Y.-N. (2018). Influence of consumers’ perceived risk on consumers’ online purchase intention. Journal of Research in Interactive Marketing, 12(3), 309–327. https://doi.org/https://doi.org/10.1108/JRIM-11-2017-0100
   Google Scholar
• Katta, R. M. R., & Patro, C. S. (2017). Influence of web attributes on consumer purchase intentions. International Journal of Sociotechnology and Knowledge Development, 9(2), 1–16. https://doi.org/https://doi.org/10.4018/IJSKD.2017040101
   Google Scholar
• Kemp, S. (2019). Digital 2019: Global internet use accelerates. https://wearesocial.com/blog/2019/01/digital-2019-global-internet-use-accelerates
   Google Scholar
• Khan, F., Rasli, A., Yusoff, R., & Isa, K. (2015). Impact of trust on online shopping: A systematic review of literature. Journal of Advanced Review on Scientific Research, 8(1), 1–8.
   Google Scholar
• Khan, M. A. S., Du Jianguo, A. M., Saleem, S., Boamah, K. B., Javed, U., & Usman, M. (2019). Rejuvenating the concept of work alienation through job demands-resources model and examining its relationship with emotional exhaustion and explorative and exploitative learning. Psychology Research and Behavior Management, 12, 931–941. https://doi.org/https://doi.org/10.2147/PRBM.S204193
   Google Scholar
• Kim, S., & Park, H. (2013). Effects of various characteristics of social commerce (s-commerce) on consumers’ trust and trust performance. International Journal of Information Management, 33(2), 318–332. https://doi.org/https://doi.org/10.1016/j.ijinfomgt.2012.11.006
   Google Scholar
• Kim, Y., & Peterson, R. A. (2017). A meta-analysis of online trust relationships in e-commerce. Journal of Interactive Marketing, 38, 44–54. https://doi.org/https://doi.org/10.1016/j.intmar.2017.01.001
   Google Scholar
• Kim, Y. J., Han, S. M., & Lee, E. (2014). The role of trust in online shopping malls: Different types of trust and how they affect consumer intention. International Journal of Electronic Commerce Studies, 4(2), 355–358. https://doi.org/https://doi.org/10.7903/ijecs.1127
   Google Scholar
• Kleinlercher, K., Emrich, O., Herhausen, D., Verhoef, P. C., & Rudolph, T. (2018). Websites as information hubs: How informational channel integration and shopping benefit density interact in steering customers to the physical store. Journal of the Association for Consumer Research, 3(3), 330–342. https://doi.org/https://doi.org/10.1086/698415
   Google Scholar
• Kock, N., & Hadaya, P. (2018). Minimum sample size estimation in PLS-SEM: The inverse square root and gamma-exponential methods. Information Systems Journal, 28(1), 227–261. https://doi.org/https://doi.org/10.1111/isj.12131
   Google Scholar
• Lee, T. S., Ariff, M. S. M., Zakuan, N., Sulaiman, Z., & Saman, M. Z. M. (2016). Online sellers’ website quality influencing online buyers’ purchase intention. [ Paper presentation] IOP Conference Series: Materials Science and Engineering, Bali, Indonesia.
   Google Scholar
• Lien, C.-H., Cao, Y., & Zhou, X. (2017). Service quality, satisfaction, stickiness, and usage intentions: An exploratory evaluation in the context of WeChat services. Computers in Human Behavior, 68, 403–410. https://doi.org/https://doi.org/10.1016/j.chb.2016.11.061
   Google Scholar
• Luo, S.-F., & Lee, T.-Z. (2011). The influence of trust and usefulness on customer perceptions of e-service quality. Social Behavior and Personality: An International Journal, 39(6), 825–837. https://doi.org/https://doi.org/10.2224/sbp.2011.39.6.825
   Google Scholar
• MacKinnon, D. P., Lockwood, C. M., Hoffman, J. M., West, S. G., & Sheets, V. (2002). A comparison of methods to test mediation and other intervening variable effects. Psychological Methods, 7(1), 83–104. https://doi.org/https://doi.org/10.1037/1082-989X.7.1.83
   Google Scholar
• Manfreda, K. L., Bosnjak, M., Berzelak, J., Haas, I., & Vehovar, V. (2008). Web surveys versus other survey modes: A meta-analysis comparing response rates. International Journal of Market Research, 50(1), 79–104. https://doi.org/https://doi.org/10.1177/147078530805000107
   Google Scholar
• Mao, D. (2010). A study of consumer trust in internet shopping and the moderating effect of risk aversion in mainland China [BA dissertation]. Hong Kong Baptist University. http://libproject.hkbu.edu.hk/trsimage/hp/07050526.pdf
   Google Scholar
• Matthews, L., Hair, J., & Matthews, R. (2018). PLS-SEM: The holy grail for advanced analysis. Marketing Management Journal, 28(1), 1–13.
   Google Scholar
• McDonald, R. P. (1996). Path analysis with composite variables. Multivariate Behavioral Research, 31(2), 239–270. https://doi.org/https://doi.org/10.1207/s15327906mbr3102_5
   Google Scholar
• Mohseni, S., Jayashree, S., Rezaei, S., Kasim, A., & Okumus, F. (2018). Attracting tourists to travel companies’ websites: The structural relationship between website brand, personal value, shopping experience, perceived risk and purchase intention. Current Issues in Tourism, 21(6), 616–645. https://doi.org/https://doi.org/10.1080/13683500.2016.1200539
   Google Scholar
• Nunnally, J. (1978). Psychometric Methods. McGraw-Hill.
   Google Scholar
• Oghazi, P., Karlsson, S., Hellström, D., & Hjort, K. (2018). Online purchase return policy leniency and purchase decision: Mediating role of consumer trust. Journal of Retailing and Consumer Services, 41, 190–200. https://doi.org/https://doi.org/10.1016/j.jretconser.2017.12.007
   Google Scholar
• Pawlasová, P., & Klézl, V. (2017). Factors affecting Generation Y customers’ satisfaction with online group‑buying purchases in South Korea. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, 65(6), 2045–2054. https://doi.org/https://doi.org/10.11118/actaun201765062045
   Google Scholar
• Pelaez, A., Chen, C.-W., & Chen, Y. X. (2019). Effects of perceived risk on intention to purchase: A meta-analysis. Journal of Computer Information Systems, 59(1), 73–84. https://doi.org/https://doi.org/10.1080/08874417.2017.1300514
   Google Scholar
• Pham, Q., Tran, X., Misra, S., Maskeliūnas, R., & Damaševičius, R. (2018). Relationship between convenience, perceived value, and repurchase intention in online shopping in Vietnam. Sustainability, 10(1), 1–14. https://doi.org/https://doi.org/10.3390/su10010156
   Google Scholar
• Podsakoff, P., MacKenzie, S., Lee, J.-Y., & Podsakoff, N. (2003). Common method biases in behavioral research: A critical review of the literature and recommended remedies. Journal of Applied Psychology, 8(5), 879–903. https://doi.org/https://doi.org/10.1037/0021-9010.88.5.879
   Google Scholar
• Qureshi, I., Fang, Y., Ramsey, E., McCole, P., Ibbotson, P., & Compeau, D. (2009). Understanding online customer repurchasing intention and the mediating role of trust–an empirical investigation in two developed countries. European Journal of Information Systems, 18(3), 205–222. https://doi.org/https://doi.org/10.1057/ejis.2009.15
   Google Scholar
• Regner, T., & Riener, G. (2017). Privacy is precious: On the attempt to lift anonymity on the internet to increase revenue. Journal of Economics & Management Strategy, 26(2), 318–336. https://doi.org/https://doi.org/10.1111/jems.12192
   Google Scholar
• Rigdon, E. E., Schumacker, R. E., & Wothke, W. (1998). A comparative review of interaction and nonlinear modeling. In R. E. Schumacker (Ed.), Interaction and Nonlinear Effects in Structural Equation Modeling (pp. 1–16). Taylor & Francis.
   Google Scholar
• Ringle, C. M., Sarstedt, M., & Straub, D. (2012). A critical look at the use of PLS-SEM in MIS Quarterly. MIS Quarterly, 36(1), 3–14. https://doi.org/https://doi.org/10.2307/41410402
   Google Scholar
• Ringle, C. M., Wende, S., & Becker, J.-M. (2015). SmartPLS 3. SmartPLS GmbH.
   Google Scholar
• Rosa, R. P., Qomariah, N., & Tyas, W. M. (2018). Impact of social commerce characteristics on consumer trust on online shop in Instagram. Prosiding CELSciTech, 3, 80–88.
   Google Scholar
• Sahoo, N., Dellarocas, C., & Srinivasan, S. (2018). The impact of online product reviews on product returns. Information Systems Research, 29(3), 723–738. https://doi.org/https://doi.org/10.1287/isre.2017.0736
   Google Scholar
• Saleh, K. (2019). Global Online retail spending – Statistics and trends. https://www.invespcro.com/blog/global-online-retail-spending-statistics-and-trends/
   Google Scholar
• Salisbury, W. D., Pearson, R. A., Pearson, A. W., & Miller, D. W. (2001). Perceived security and World Wide Web purchase intention. Industrial Management & Data Systems, 101(4), 165–177. https://doi.org/https://doi.org/10.1108/02635570110390071
   Google Scholar
• Sattar, S., & Ameer, M. H. (2014). Online shopping adaptation by individuals in Pakistan. International Institute for Science, Technology and Education, 4(3), 99–103.
   Google Scholar
• Shafiee, M. M., & Bazargan, N. A. (2018). Behavioral customer loyalty in online shopping: The role of e-service quality and e-recovery. Journal of Theoretical and Applied Electronic Commerce Research, 13(1), 26–38. https://doi.org/https://doi.org/10.4067/S0718-18762018000100103
   Google Scholar
• Sharma, A., & Bahl, S. (2018). Influence of service quality of e-commerce websites on customers’ trust, commitment and loyalty: A case of Indian customers. International Journal of Research in Engineering, IT and Social Sciences, 8(9), 75–84.
   Google Scholar
• Stouthuysen, K., Teunis, I., Reusen, E., & Slabbinck, H. (2018). Initial trust and intentions to buy: The effect of vendor-specific guarantees, customer reviews and the role of online shopping experience. Electronic Commerce Research and Applications, 27, 23–38. https://doi.org/https://doi.org/10.1016/j.elerap.2017.11.002
   Google Scholar
• Suryadi, N., Suryana, Y., Komaladewi, R., & Sari, D. (2018). Consumer, customer and perceived value: Past and present. Academy of Strategic Management Journal, 17(4), 1–9.
   Google Scholar
• Tandon, U., Kiran, R., & Sah, A. N. (2018). The influence of website functionality, drivers and perceived risk on customer satisfaction in online shopping: An emerging economy case. Information Systems and e-Business Management, 16(1), 57–91. https://doi.org/https://doi.org/10.1007/s10257-017-0341-3
   Google Scholar
• Tarhini, A., Alalwan, A. A., Al-Qirim, N., & Algharabat, R. (2018). An analysis of the factors influencing the adoption of online shopping. International Journal of Technology Diffusion, 9(3), 68–87. https://doi.org/https://doi.org/10.4018/IJTD.2018070105
   Google Scholar
• Thomas, M. R., Kavya, V., & Monica, M. (2018). Online website cues influencing the purchase intention of Generation Z mediated by trust. Indian Journal of Commerce and Management Studies, 9(1), 13–23. https://doi.org/https://doi.org/10.18843/ijcms/v9i1/03
   Google Scholar
• Truong, N. B., Lee, H., Askwith, B., & Lee, G. M. (2017). Toward a trust evaluation mechanism in the social internet of things. Sensors, 17(6), 1–24. https://doi.org/https://doi.org/10.3390/s17061346
   Google Scholar
• Wong, K.-K.-K. (2013). Partial least squares structural equation modeling (PLS-SEM) techniques using SmartPLS. Marketing Bulletin, 24(1), 1–32.
   Google Scholar
• Wu, J.-J., Hwang, J.-N., Sharkhuu, O., & Tsogt-Ochir, B. (2018). Shopping online and off-line? Complementary service quality and image congruence. Asia Pacific Management Review, 23(1), 30–36. https://doi.org/https://doi.org/10.1016/j.apmrv.2017.01.004
   Google Scholar
• Wu, W.-Y., & Chang, M.-L. (2007). The role of risk attitude on online shopping: Experience, customer satisfaction, and repurchase intention. Social Behavior and Personality: An International Journal, 35(4), 453–468. https://doi.org/https://doi.org/10.2224/sbp.2007.35.4.453
   Google Scholar
• Yoon, S.-J. (2002). The antecedents and consequences of trust in online-purchase decisions. Journal of Interactive Marketing, 16(2), 47–63. https://doi.org/https://doi.org/10.1002/dir.10008
   Google Scholar
• Yuen, K. F., Wang, X., Wong, Y. D., & Zhou, Q. (2018). The effect of sustainable shipping practices on shippers’ loyalty: The mediating role of perceived value, trust and transaction cost. Transportation Research Part E: Logistics and Transportation Review, 116, 123–135. https://doi.org/https://doi.org/10.1016/j.tre.2018.06.002
   Google Scholar