Lukanov, Hristo, Ivelina Pavlova, Atanas Genchev, and Todor Petrov. “Egg Production Characteristics of Several Bulgarian Chicken Breeds”. Genetic Resources 6, no. 12 (October 30, 2025): 120–129. Accessed December 16, 2025. https://www.genresj.org/index.php/grj/article/view/genresj.QNIV2785.