1. L. Bailey, B.V. Ball, Honeybee Pathology, second ed., Academic Press, London, 1991, p. 193.
2. J.W. Boot, J.N.M. Calis, J. Beetsma, Proceedings of the Section of Experimental and Applied Entomology of the Netherlands Entomological Society (N.E.V), vol. 2, 1991, p. 154.
3. Weight Loss and Other Damage to Developing Worker Honeybees from Infestation withVarroa Jacobsoni