Lyutskanov, M., Urumova, V., & Koev, K. (2011). EPIDEMIOLOGICAL EVIDENCE OF CALF NEONATAL COLIBACTERIOSIS IN LARGE INTESIVE DAIRY FARMS. Bulgarian Journal of Animal Husbandry, 48(6), 35-42. https://agriacad.eu/ojs/index.php/bjah/article/view/669