Smith, W. D.; Bizzarro, J. J.; Richards, V. P.; Nielsen, J.; Márquez-Flarías, F.; Shivji, M. S. (2009-09-01). "Morphometric convergence and molecular divergence: the taxonomic status and evolutionary history of Gymnura crebripunctata and Gymnura marmorata in the eastern Pacific Ocean". Journal of Fish Biology. 75 (4): 761–783. doi:10.1111/j.1095-8649.2009.02300.x. ISSN1095-8649. PMID20738578.
Smith, W. D.; Bizzarro, J. J.; Richards, V. P.; Nielsen, J.; Márquez-Flarías, F.; Shivji, M. S. (2009-09-01). "Morphometric convergence and molecular divergence: the taxonomic status and evolutionary history of Gymnura crebripunctata and Gymnura marmorata in the eastern Pacific Ocean". Journal of Fish Biology. 75 (4): 761–783. doi:10.1111/j.1095-8649.2009.02300.x. ISSN1095-8649. PMID20738578.
Smith, W. D.; Bizzarro, J. J.; Richards, V. P.; Nielsen, J.; Márquez-Flarías, F.; Shivji, M. S. (2009-09-01). "Morphometric convergence and molecular divergence: the taxonomic status and evolutionary history of Gymnura crebripunctata and Gymnura marmorata in the eastern Pacific Ocean". Journal of Fish Biology. 75 (4): 761–783. doi:10.1111/j.1095-8649.2009.02300.x. ISSN1095-8649. PMID20738578.