1. Akre, R. D., Garnett, W. B., MacDonald, J. F., Greene, A., and Landolt, P. (1976). Behavior and colony development ofVespula pensylvanica andV. atropilosa (Hymenoptera Vespidae).J. Kans. Entomol. Soc. 49: 63–84.
2. Archer, M. E. (1980). Population dynamics. In Edwards, R. E. (ed.),Social Wasps, Their Biology and Control, Rentokil, Sussex, pp. 172–207.
3. Brockmann, H. J. (1993). Parasitizing conspecifics: Comparison between Hymenoptera and Birds.TREE 8(1): 2–4.
4. Cervo, R., and Dani, F. R. (1993). Social parasitism and its evolution inPolistes. International workshop: The Paper Wasp Case. Natural History and the Evolution of an Animal Society, Castiglioncello, Italy.
5. Dani, F. R., and Cervo, R. (1992). Reproductive strategies following nest loss inPolistes gallicus (Hymenoptera Vespidae).Ethol. Ecol. Evol. 2: 49–53.