1. Antrobus, S. 1992. Population genetics and ecology of colonising and established populations of Primula veris Ph.D. Thesis, Oxford Polytechnic.
2. Barrett, S C H, and Husband, B C. 1990. The genetics of plant migration and colonization. In: Brown, A. H. D., Clegg, M. T., Kahler, A. L. and Weir, B. S. (eds) Plant Population Genetics, Breeding and Genetic Resources Sinauer Associates Inc., Massachusetts, pp. 254–277.
3. Boyd, M, Silvertown, J, and Tucker, C. 1990. Population ecology of heterostyle and homostyle Primula vulgaris: growth, survival and reproduction in field populations. J Ecol, 78, 799–813.
4. Brown, A H D. 1979. Enzyme polymorphism in plant populations. Theor Pop Biol, 15, 1–42.
5. Brown, A H D, and Marshall, D R. 1981. Evolutionary changes accompanying colonization in plants. In: Scudder, G. G. E. and Reveal, J. L. (eds) Evolution Today, Carnegie-Mellon University, Pittsburgh, pp. 351–363.