Santos, M.C.O., Cremer, M.J., Secchi, E.R., Flach, L., Filla, G., Hubner, A. and Dussán-Duque, S. 2010. Report of the Working Group on Population Abundance and Density Estimation. Latin American Journal of Aquatic Mammals. 8, 1-2 (Dec. 2010), 39-45. DOI:https://doi.org/10.5597/lajam00152.