RT Journal Article SR Electronic T1 Preventive treatment of tuberculin-negative contacts JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 497 OP 498 VO 109 IS 6 A1 Brickman, H. F. A1 Beaudry, P. H. YR 1973 UL http://www.cmaj.ca/content/109/6/497.abstract