1 Pulmonary Center, Boston University School of Medicine, Boston, MA. Electronic address: [email protected].
2 Pulmonary Center, Boston University School of Medicine, Boston, MA.
3 Alumni Medical Library, Boston University School of Medicine, Boston, MA.
4 Pulmonary Center, Boston University School of Medicine, Boston, MA; Center for Healthcare Organization and Implementation Research, Edith Nourse Rogers Memorial Veterans Hospital, Bedford, MA.