VASILEVA, VILIANA, TODOR KERTIKOV, and ANNA ILIEVA. 2017. “DRY MASS YIELD AND AMOUNT OF FIXED NITROGEN IN SOME FORAGE LEGUME CROPS AFTER TREATMENT WITH ORGANIC FERTILIZER HUMUSTIM”. Bulgarian Journal of Agricultural Science 23 (5): 816-19. https://agriacad.eu/ojs/index.php/bjas/article/view/5593.