“Volumetric and Material Balance Methods of Reserve Estimation: A Comparative Study Using Niger Delta Reservoirs”. International Journal of Engineering Research and Advanced Technology (ijerat) (E-ISSN 2454-6135) DOI: 10.31695/IJERAT 4, no. 9 (September 5, 2018): 42–52. Accessed April 28, 2024. https://ijerat.com/index.php/ijerat/article/view/395.