Orugba, H.O. et al. 2021. Production of Biodiesel from a Novel Combination of Raphia Africana Kernel Oil and Turtle Shell (Centrochelys Sulcata) Heterogenous Catalyst. Journal of Human, Earth, and Future. 2, 3 (Sep. 2021), 258–268. DOI:https://doi.org/10.28991/HEF-2021-02-03-07.