APA aipamena

Hopewell, S., & Clarke, M. (2004). Impact of grey literature on systematic reviews of randomized trials.

Chicago Style aipamena

Hopewell, S., and M. Clarke. Impact of Grey Literature on Systematic Reviews of Randomized Trials. 2004.

MLA aipamena

Hopewell, S., and M. Clarke. Impact of Grey Literature on Systematic Reviews of Randomized Trials. 2004.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.