RT Journal Article SR Electronic T1 Harp seal heart valves being tested for human use JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 1290 OP 1291 DO 10.1503/cmaj.090936 VO 180 IS 13 A1 Roger Collier YR 2009 UL http://www.cmaj.ca/content/180/13/1290.abstract