J. Nyéki, Z. Szabó, T. Szabó, and M. Soltész, “Morphological and phenological properties of sour cherry varieties grown in Hungary and their inter-incompatibility relations”, Int. j. hortic. sci., vol. 6, no. 1, pp. 114–117., Feb. 2000, doi: 10.31421/IJHS/6/1/80.