Martin, FW; Ortiz, Sonia. Origin and Anatomy of Tubers of Dioscorea Floribunda and D. Spiculiflora. Botanical Gazette. 1963, 124 (6): 416–421. JSTOR 2473209. doi:10.1086/336228.
J. Allemann; P.J. Robbertse; P.S. Hammes. Organographic and anatomical evidence that the edible storage organs of Plectranthus esculentus N.E.Br. (Lamiaceae) are stem tubers. Field Crops Research. 20 June 2003, 83 (1): 35–39. doi:10.1016/S0378-4290(03)00054-6.
Martin, FW; Ortiz, Sonia. Origin and Anatomy of Tubers of Dioscorea Floribunda and D. Spiculiflora. Botanical Gazette. 1963, 124 (6): 416–421. JSTOR 2473209. doi:10.1086/336228.