Otobo G, Endurance Fegor Isoje, Augustina Ufuoma Igbuku. Hazardous Nature of Native Chalk (Calabash chalk). IJSBAR [Internet]. 2023 Oct. 30 [cited 2024 Jul. 3];71(1):31-6. Available from: https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/16177