Potency trends of Δ9-THC and other cannabinoids in confiscated Cannabis preparations from 1993–2008. - Mehmedic,Z.; Chandra,S.; Slade,D.; Denham,H.; Foster,S.; Patel,A.S.; Ross,S.A.; Khan,I.A.; ElSohly,M.A. (J Forensic Sci, 2010)