Onojake และผู้แต่งคนอื่นๆ. (2013) Geochemical Appraisal of Crude Oils from Umutu and Bomu Fields in the Niger Delta. <i>Bulletin of Earth Sciences of Thailand (BEST)</i>, <i>6</i>(1), 31-39.Onojake และผู้แต่งคนอื่นๆ. "Geochemical Appraisal of Crude Oils from Umutu and Bomu Fields in the Niger Delta". Bulletin of Earth Sciences of Thailand (BEST) 6 (2013):31-39.Onojake และผู้แต่งคนอื่นๆ. Geochemical Appraisal of Crude Oils from Umutu and Bomu Fields in the Niger Delta. Department of Geology, Chulalongkorn University:ม.ป.ท. 2013.