1. Broertjes, C., 1968. Mutation breeding of vegetatively propagated crops. Fifth Eucarpia Congr. Milano: 139–165.
2. Broertjes, C., 1969. Mutation breeding of Streptocarpus. Euphytica 18: 333–339.
3. Broertjes, C., 1971. Possibilities of mutation breeding in ornamentals. Eucarpia Meet. Ornamentals, Wageningen: 7–15.
4. Broertjes, C., 1972. Significance for practical plant breeding of acute, chronic and fractionated doses of X-rays and fast neutrons. Experiments using the adventitious bud technique with Saintpaulia ionantha H. Wendl. Thesis (in press).
5. Broertjes, C., Haccius, B. & Weidlich, S., 1968. Adventitious bud formation on isolated leaves and its significance for mutation breeding. Euphytica 17: 321–344.