Holger J Schünemann , Brydon JB Grant , Jo L Freudenheim , Paola Muti , Susan E McCann , Deepa Kudalkar , Malathi Ram , Tom Nochajski , Marcia Russell and Maurizio Trevisan
BMC Pulmonary Medicine 2002, 2:3doi:10.1186/1471-2466-2-3