Bhargavi Chinta, and Madhavi Nannapaneni. 2015. “Preparation of O- Palmitoyl Pullulan Micro Spheres for the Controlled Release of Hydrophillic Drug: Verapamil Hydrochloride”. World Journal of Pharmaceutical Sciences 3 (5):941-57. https://wjpsonline.com/index.php/wjps/article/view/synthesis-palmitoyl-pullulan-micro-spheres-verapamil.