1. Effect of diet, level, and source of xantophyll on hen performance and egg yolk pigmentation;Angeles M;Official Journal of the Poultry Science Association,1998
2. Nutrição Animal: as bases e os fundamentos de nutrição animal, os alimentos;Andriguetto JM,1998
3. Influence of type and source of xanthophylls and level of use on yolk pigmentation;Baião NC
4. Effect of carophyll yellow and carophyll red added to comercial feeds for laying hens on yolk colour and its stability during short-term refrigeration;Gawecki K;Roczniki Akademii Rolniczez W Poznaniu,1977
5. The effect of synthetic pigment addition to feed on the color of hen egg yolk;Halaj M;Czech Journal of Animal Science,1999