1. Bateson, P. (1983). Optimal outbreeding. Mate Choice, 257, 277.
2. Beukeboom, L. W. (1994). Phenotypic fitness effects of the selfish B chromosome, paternal sex ratio (PSR) in the parasitic wasp Nasonia vitripennis. Evolutionary Ecology, 8(1), 1–24.
3. Butlin, R. (1989). Reinforcement of premating isolation. In D. Otte & J. A. Endler (Eds.), Speciation and its consequences (pp. 158–179). Sinauer Associates: Sunderland.
4. Butlin, R. K., & Tregenza, T. (1997). In speciation no accident. Nature, London, 387, 551–552.
5. Dobzhansky, T. H. (1936). Studies on hybrid sterility. II. Localization of sterility factors in Drosophila pseudoobscura hybrids. Genetics, 21(2), 113.