MANOLOVA, V.; KOSTADINOVA, S.; MANOLOV, I. ECONOMIC EFFICIENCY OF FERTILIZATION AND ITS RESIDUAL-EFFECT DURING CONVERSION PERIOD TO ORGANIC FIELD CROP PRODUCTION. Bulgarian Journal of Agricultural Science, Sofia, BG, v. 21, n. 5, p. 1022–1026, 2015. Disponível em: https://agriacad.eu/ojs/index.php/bjas/article/view/5500.. Acesso em: 4 nov. 2026.