McEachran, J.D.; Dunn, K.A.; Miyake, T. (1996). "Interrelationships within the batoid fishes (Chondrichthyes: Batoidea)". In Stiassney, M.L.J.; Parenti, L.R.; Johnson, G.D. (eds.). Interrelationships of Fishes. Academic Press. pp. 63–84. ISBN978-0-12-670951-3.
Heemstra, P.C.; Smith, M.M. (1980). "Hexatrygonidae, a new family of stingrays (Myliobatiformes: Batoidea) from South Africa, with comments on the classification of batoid fishes". Ichthyological Bulletin (J. L. B. Smith Institute of Ichthyology). 43: 1–17. hdl:10962/d1019701.