1. Royal Commission: The release of genetically engineered organisms to the environment. Her Majesty's Stationary Office, London 1989
2. National Research Council: Field testing genetically modified organisms: framework for decisions. Washington D.C.: National Acad. Press 1989
3. Bio-Engineering5, Heft 6 (1989)
4. Markl, H.: AvH-Magazin54, 3 (1989)
5. Mohr, H.: Natur und Moral. Ethik in der Biologie. Darmstadt: Wiss. Buchgesellschaft 1987