Dyfyniad APA

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

Dyfyniad Arddull Chicago

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

Dyfyniad MLA

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

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.