1. Anon., 2002 . Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc . p339 -440 . Available fromhttp://books.nap.edu/books/0309072794/html/index.html. Accessed 5/9/02.
2. EW. Becker, 1994 . Microalgae biotechnology and microbiology . Cambridge, U.K.: Cambridge Univ. Press. 293 p.
3. H Belcher, and E. Swale, 1982 . A guide for schools and colleges. Institute of Terrestria Ecology, Culture Centre of Algae and Protozoa, Cambridge . Cambridge, U.K.: University Press. p22 .