DOE:10.1378/chest.09-1777
DOE:10.1378/chest.11-0981
DOE:10.1378/chest.78.2.395
DOE:10.1378/chest.83.5_Supplement.31S
DOE:10.1378/chest.99.3_Supplement.28S-a
DOE:10.1378/chest.100.4.903