RT Journal Article SR Electronic T1 Canadian baby boomers shirk safe sex JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP E827 OP E828 DO 10.1503/cmaj.109-3729 VO 182 IS 18 A1 Lauren Vogel YR 2010 UL http://www.cmaj.ca/content/182/18/E827.abstract