@article{sohail_khan_shahzad_hussain_ranjha_2014,  title={pH-sensitive polyvinylpyrrolidone-acrylic acid hydrogels: Impact of material parameters on swelling and drug release},  volume={50},  ISSN={1984-8250},  url={https://doi.org/10.1590/S1984-82502011000100018},  DOI={10.1590/S1984-82502011000100018},  number={1},  journal={Brazilian Journal of Pharmaceutical Sciences},  publisher={Universidade de São Paulo, Faculdade de Ciências Farmacêuticas},  author={Sohail, Kashif and Khan, Ikram Ullah and Shahzad, Yasser and Hussain, Talib and Ranjha, Nazar Muhammad},  year={2014},  month={Jan},  pages={173–184} }