@article{taha_draz_gamal_ibrahim_2021,  title={Adding autogenic drainage to chest physiotherapy after upper abdominal surgery: effect on blood gases and pulmonary complications prevention. Randomized controlled trial},  volume={139},  ISSN={1516-3180},  url={https://doi.org/10.1590/1516-3180.2021.0048.0904221},  DOI={10.1590/1516-3180.2021.0048.0904221},  number={6},  journal={Sao Paulo Medical Journal},  publisher={Associação Paulista de Medicina - APM},  author={Taha, Mona Mohamed and Draz, Ramy Salama and Gamal, Mohamed Mostafa and Ibrahim, Zizi Mohamed},  year={2021},  month={Nov},  pages={556–563} }