RT Journal Article SR Electronic T1 Experts question timing of vaccination against shingles JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 869 OP 869 DO 10.1503/cmaj.109-4502 VO 185 IS 10 A1 Lauren Kramer YR 2013 UL http://www.cmaj.ca/content/185/10/869.abstract AB