@inbook {20, title = {Phylogeny of the Batoidea}, booktitle = {Biology of sharks and their relatives}, year = {2004}, pages = {79-113}, publisher = {CRC Press}, organization = {CRC Press}, author = {J.D. McEachran and Aschliman N and J.C. Carrier and J.A. Musick and M.R. Heithaus} }