The Effects of Using Pretreated Cotton Gin Trash on the Production of Biogas from Anaerobic Co-Digestion with Cow Manure and Sludge oleh Muhammad Usman Hanif, Mohammed Zwawi, Mohammed Algarni, Ali Bahadar, Hamid Iqbal, Sergio C. Capareda, Muhammad Adnan Hanif, Adeel Waqas, Nazia Hossain, Muhammad Tahir Hussain Siddiqui, Sabzoi Nizamuddin, Asma Jamil