Hafeez, N., Q. Ullah, A. Hanif, Z. Akhtar, M. . Umar, and R. Rafaqat. “Frequency of Clinical Symptoms of Gastroesophageal Reflux Disease in Asthmatic Patients”. The International Journal of Frontier Sciences, vol. 3, no. 1, Jan. 2019, pp. 3-9, doi:10.37978/tijfs.v3i1.43.