@article{tiwari_srivastava_tiwari_rai_2009,  title={Extended release promethazine HCl using acrylic polymers by freeze-drying and spray-drying techniques: formulation considerations},  volume={45},  ISSN={1984-8250},  url={https://doi.org/10.1590/S1984-82502009000400029},  DOI={10.1590/S1984-82502009000400029},  number={4},  journal={Brazilian Journal of Pharmaceutical Sciences},  publisher={Universidade de São Paulo, Faculdade de Ciências Farmacêuticas},  author={Tiwari, Ruchi and Srivastava, Birendra and Tiwari, Gaurav and Rai, Awanik},  year={2009},  month={Oct},  pages={829–840} }