Pompa, S., Ehrlich, P. R. & Ceballos, G. (2011) "Global distribution and conservation of marine mammals". PNAS 108 (33): 13600–13605 DOI:10.1073/pnas.1101525108
Kaschner, K., Tittensor, D. P., Ready, J., Gerrodette, T. & Worm, B. (2011) "Current and Future Patterns of Global Marine Mammal Biodiversity" PLoS ONE 6(5): 19653 DOI:10.1371/journal.pone.0019653
Shipper, J., Chanson, J. S. & Chiozza, F. et al (2008) "The Status of the World’s Land and Marine Mammals: Diversity, Threat, and Knowledge" Science 322: 225-230 DOI:10.1126/science.1165115