REFERENCES
- APHA, Standard Methods for Examination of Water and Wastewater. American Public Health Association, Washington DC, 1989.
- Bick H. (1972) Ciliated protozoa—An illustrated guide to the species used as biological indicators in freshwater biology, WHO, Geneva, 1–198.
- Curds C. (1969) An illustrated key to the British Freshwater Ciliated Protozoa community found in activated sludge, Br. l. London, 1–90.
- Keith L.N., Telliard W.A. (1979) Priority pollutants—a perspective view, ES & T, 13, 416–425.
- Kutikova L. (1970) The Rotifers of the USSR Fauna (Rotifera), Nauka, Leningrad, 1–741 (in russian).
- Luna-Pabello P.M., Aladro-Lubel M.A., Duran-de-Bazua C. (1996) Journal for industrial Microbiology, 17, 62–68.
- Sladecek V. (1973) Arch, fur Hydrobiol., Supply 7, Germany, 1–217.
- Topalova Y., R.D. Kozuharov (1999) Waste Management, 19, 247–254.
- Topalova Y., Dimkov R., Ivanov I., Sergieva S., Arsov R. (1998) Biotechnol. and Biotechnol. Eq., 12, 91–95.
- Wanner J. (1994) Wat. Sci. & Tech, 30, 159–169.