Kulaga Sophie N, Karp Igor
Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec H3A 1A2, Canada.
Department of Medicine, McGill University, Montreal, Quebec H3A 1A2, Canada.
Lancet. 2007 Mar 3;369(9563):738-739. doi: 10.1016/S0140-6736(07)60352-3.