Tawfiq, S., Majeed Khursheed, A. and Khalil Abdulla, T. 2013. Determination of vanadium in Natural gas using graphite furnace atomic absorption spectrometry (GFAAS). Journal of Education and Science. 26, 5 (Dec. 2013), 64–74. DOI:https://doi.org/10.33899/edusj.2013.163056.