This paper is in the following e-collection/theme issue:

Medicine 2.0: Social Media, Open, Participatory, Collaborative Medicine 

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Works citing "Effects of Internet Popular Opinion Leaders (iPOL) Among Internet-Using Men Who Have Sex With Men"

Nai-Ying Ko, Chao-Hsien Hsieh, Ming-Chi Wang, Chiang Lee, Chun-Lin Chen, An-Chun Chung, Su-Ting Hsu
J Med Internet Res 2013 (Feb 25); 15(2):e40 

According to Crossref, the following articles are citing this article (DOI 10.2196/jmir.2264):

(note that this is only a small subset of citations)

1. Curtis BL. Social Networking and Online Recruiting for HIV Research. Journal of Empirical Research on Human Research Ethics: An International Journal 2014;9(1):58 [CrossRef]