ŽITŇAN, Rudolf et al. The effect of probiotic microorganisms on rumen metabolism. In Pediatria. International probiotic conference : probiotics for the 3rd millennium : june 4th-7th 2008 Hotel Bellevue High Tatras Slovakia, 2008, roč. 3, č. S3, s. 58 S. ISSN 1336-863X. Bratislava : SAMEDI.