1. Allen, W R, and Sheppard, P M. 1971. Copper tolerance in some Californian populations of the monkey flower Mimulus guttatus. Proc R Soc B, 177, 177–196.
2. Antonovics, J. 1966. The genetics and evolution of differences between closely adjacent plant populations with special reference to heavy metal tolerance. Ph.D. Thesis, University of Wales.
3. Antonovics, J. 1968. Evolution in closely adjacent plant populations. V. Evolution of self-fertility. Heredity, 23, 219–238.
4. Antonovics, J, Bradshaw, A D, and Turner, R G. 1971. Heavy metal tolerance in plants. Adv Ecol Res 7, 1–85.
5. Bröker, W. 1963. Genetisch-Physiologische Untersuchungen über die Zinkverträglichkeit von Silene inflata. Sm. Flora, 153, 122–156.