[1] COLUMBIA UNIV COLL PHYS & SURG,SCH PUBL HLTH,DIV EPIDEMIOL,NEW YORK,NY 10032
[2] COLUMBIA UNIV COLL PHYS & SURG,DEPT PATHOL,NEW YORK,NY 10032
[3] INST CANC RES,CHESTER BEATTY LABS,CRC CTR CELL & MOL BIOL,LONDON SW3 6JB,ENGLAND
[4] INST CANC RES,CHESTER BEATTY LABS,VIROL LAB,LONDON SW3 6JB,ENGLAND