Newton, Leonard E. (2002). "A new species of Encephalartos (Zamiaceae) in Sudan". Botanical Journal of the Linnean Society. 140 (2): 187–192. doi:10.1046/j.1095-8339.2002.00094.x. ISSN1095-8339.
Newton, Leonard E. (2002). "A new species of Encephalartos (Zamiaceae) in Sudan". Botanical Journal of the Linnean Society. 140 (2): 187–192. doi:10.1046/j.1095-8339.2002.00094.x. ISSN1095-8339.