Sibbald, B. (2001). Doctors asked to take pledge to shun drug company freebies.
Čikaški stil citiranjaSibbald, Barbara. Doctors Asked to Take Pledge to Shun Drug Company Freebies. 2001.
MLA način citiranjaSibbald, Barbara. Doctors Asked to Take Pledge to Shun Drug Company Freebies. 2001.
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