RT Journal Article SR Electronic T1 The origin, structure, and pharmacological activity of botulinum toxin. JF Pharmacological Reviews JO Pharmacol Rev FD American Society for Pharmacology and Experimental Therapeutics SP 155 OP 188 VO 33 IS 3 A1 L L Simpson YR 1981 UL http://pharmrev.aspetjournals.org/content/33/3/155.abstract AB