R. Nimnu, J, et al. “Foraminiferal Biostratigrpahy of Oshi-13 Field, Coastal and Central Swamp Depobelt, Niger Delta Basin, Nigeria”. International Journal of Advanced Geosciences, vol. 6, no. 1, May 2018, pp. 127-32, https://doi.org/10.14419/ijag.v6i1.10907.