Akca, Yasar, Abdulresit Brohi, and Erdinc Savas. 2016. “Differences in Mineral Contents of Apple Leaves Associated With Fruiting and Non-Fruiting of Biennial Bearing Trees”. Asian Journal of Chemistry 17 (4):2379-84. https://asianpubs.org/index.php/ajchem/article/view/13949.