1. Alt, D., 1980. Changes in the composition of the nutrient solution during plant growth—an important factor in soilless culture. Fifth International Congress on Soilless Culture. Proceedings of a Conference, 18–24 May 1980, Wageningen, The Netherlands, pp. 97–110.
2. Bedasie, S., Stewart, K.A., 1984. Effect of intermittent flow on the growth and development of lettuce cv. Salina. Sixth International Congress on Soilless Culture. Proceedings of a Conference, 29 April–5 May 1984, Lunteren, The Netherlands, pp. 139–144.
3. Burgoon, P.S., Baum, C., 1984. Year-round fish and vegetable production in a passive solar greenhouse. Sixth International Congress on Soilless Culture. Proceedings of a Conference, 29 April–5 May 1984, Lunteren, The Netherlands, pp. 151–171.
4. Use of a small-scale nutrient-film hydroponic technique to reduce mineral accumulation in aquarium water;Clarkson;Aquat. Fish. Manage.,1991
5. Douglas, J.S., 1985. Advanced Guide to Hydroponics. Pelham Books, London, 369 pp.