TY - JOUR T1 - Hua Fo tablets tainted with sildenafil-like compound JF - Canadian Medical Association Journal JO - CMAJ SP - 1568 LP - 1568 VL - 166 IS - 12 AU - Eric Wooltorton Y1 - 2002/06/11 UR - http://www.cmaj.ca/content/166/12/1568.abstract ER -