Guirguis, L. A., A. H. Mahmoud, M. A. Zahran, and M. M. Sharaf. 2014. “Oxidative Leaching Kinetics of Vanadium from Egyptian Boiler Ash under Acidic Oxidizing Conditions”. International Journal of Sciences: Basic and Applied Research (IJSBAR) 14 (1):495-505. https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/1923.