@article{articledd6533a9,
title   = {Oscillating positive expiratory pressure on respiratory resistance in chronic obstructive pulmonary disease with a small amount of secretion: a randomized clinical trial},
author = {Gastaldi, Ada Clarice and Paredi, Paolo and Talwar, Anjana and Meah, Sally and Barnes, Peter J. and Usmani, Omar S.},
year = {2015},
doi = {10.1097/MD.0000000000001845},
journal   = {Medicine}
}