Pető, Judit, Attila Hüvely, Endre Pölös, and Imre Cserni. 2014. “Leaf Macronutrient Composition of Grapes in South Plain Hungarian Vineyards”. Review on Agriculture and Rural Development 3 (1):251-55. https://analecta.hu/index.php/rard/article/view/13431.