KOTNIK, Barbara, Nežika PETRIČ, and Silvester ŽGUR. 2009. “Parameters Affecting Calving Difficulty of Charolais and Limousin Breed at the Educational and Research Centre Logatec”. Acta Agriculturae Slovenica 94 (1): 27–31. https://doi.org/10.14720/aas.2009.94.1.14819.