1. Nutritional and cultural aspects of plant species selection for a controlled ecological life support system;Hoff,1982
2. Selection of higher plant cultures for biological life support system;Milov,1975
3. The Complete Guide to Soiless Gardening;Gericke,1940
4. Hydroponics, a 1983 technology overview: a report on the current status of long-term interdisciplinary needs for research on hydroponics,;Collins,1983
5. T. W. Tibbitts, private communication (1990).