S. . Hristovski, L. Melovski, M. Šušlevska, and L. Grupče, “Belowground phytomass and production in the beech ecosystem Calamintho grandiflorae-Fagetum in Mavrovo National Park. IV. Belowground phytomass and production of herb layer”, MJEE, vol. 12, no. 1-2, pp. 3–8, Dec. 2009.