Latvia University of agriculture. (2009). Latvijas Lauksaimniecibas Universitate Raksti: Proceedings of the Latvia University of agriculture. No 22 (317).

Latvia University of agriculture. Latvijas Lauksaimniecibas Universitate Raksti: Proceedings of the Latvia University of Agriculture. No 22 (317). 2009.

Latvia University of agriculture. Latvijas Lauksaimniecibas Universitate Raksti: Proceedings of the Latvia University of Agriculture. No 22 (317). 2009.