G. Végvári and K. Hrotkó, “Anatomical study of the bud union in „Chip‘ and „T’ budded ’Jonagold’ apple trees on MM 106 rootstock”, Int. j. hortic. sci., vol. 5, no. 1-2, pp. 27–29., May 1999, doi: 10.31421/IJHS/5/1-2/17.