RT Journal Article SR Electronic T1 Tache noire JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 841 OP 841 DO 10.1503/cmaj.070102 VO 178 IS 7 A1 Nick Daneman MD A1 Robert Slinger MD YR 2008 UL http://www.cmaj.ca/content/178/7/841.abstract