The Lancet
The Lancet > 2009 > 373 > 9657 > 42-47
The Lancet > 2009 > 373 > 9657 > 31-41
The Lancet > 2009 > 373 > 9657 > 82-93
The Lancet > 2009 > 373 > 9657 > 42-47
The Lancet > 2009 > 373 > 9657 > 31-41
The Lancet > 2009 > 373 > 9657 > 82-93