Hristovski, Slavčo, et al. “Dendrochronology of Beech in the Beech Ecosystem Calamintho Grandiflorae-Fagetum in Mavrovo National Park”. Macedonian Journal of Ecology and Environment, vol. 10, no. 1, Dec. 2007, pp. 19-28, http://mjee.org.mk/index.php/mjee/article/view/79.