Lejiņš, Andris, and Biruta Lejiņa. “THE GRAIN CROP YIELD IN DIFFERENT CROP ROTATION AND EFFICIENCY OF HERBICIDES AND FUNGICIDES TREATMENT”.
ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference 1 (June 23, 2007): 125–131. Accessed May 1, 2025.
https://journals.ru.lv/index.php/ETR/article/view/1729.