CALAMASSI, R., B. MORI, F. MOSCATELLI, S. ALBERGHINI, A. BATTISTI, L. MUGNAI, and G. SURICO. “Aleppo Pine Knot Disease: Histology of the Knots, Detection of Causal Agent and Mode of Transmission”. Phytopathologia Mediterranea, vol. 47, no. 1, July 2008, pp. 61-72, doi:10.14601/Phytopathol_Mediterr-2545.