Kauser Fatema, Tauqeer Shaikh, Zahid Zaheer and S.R.Shahi 2016. Gastroretentive drug delivery system: an overview. Asian Pacific Journal of Health Sciences. 3, 4 (Dec. 2016), 131–144. DOI:https://doi.org/10.21276/apjhs.2016.3.4.22.