Carvalho, P.R. de et al. 2006. Influence of sea sources of carotenoids added to the diet of laying hens on the egg yolk pigmentation. Brazilian Journal of Veterinary Research and Animal Science. 43, 5 (Oct. 2006), 654–663. DOI:https://doi.org/10.11606/issn.1678-4456.bjvras.2006.26575.