F. Amiri, S. Yaghmaei, S. Mousavi, Comparison of Differen Methods in Bioleaching of Tungsten-rich Spent Hydro-cracking Catalyst Using Adapted Penecillum Simplicissium BBRC-20019, Chemical Engineering Transactions. 21 (2010) 1483-1488. doi:10.3303/CET1021248.