Sobiczewski, P., and T. Bubán. 2004. “The Effect of Regalis® (prohexadione Calcium) on the Reduction of Fire Blight (Erwinia Amylovora) Severity in Apple Trees”. International Journal of Horticultural Science 10 (2): 61-66. https://doi.org/10.31421/IJHS/10/2/462.