Salem, N., Mansour, A., Al-musa, A. and Al-nsour, A. 2003. Seasonal variation of Prunus necrotic ringspot virus concentration in almond, peach, and plum cultivars. Phytopathologia Mediterranea. 42, 2 (Aug. 2003), 155–160. DOI:https://doi.org/10.14601/Phytopathol_Mediterr-1708.