1. Coagulation purification of waste waters from a textile dying facility;Kozhanov;Chim. Technol. Vody,1985
2. Final coagulation purification of waste waters from aniline dying industry;Livke;Chim. Technol. Vody,1989
3. Patent No: 4301364.3, 1993. Sandoz Patent GmbH, Switzerland.
4. Purification of industrial waste waters;Bogoev;Sofia Technika,1982
5. Analysis of the performance of an industrial facility for purification of waters from azodyes;Brazhenko;Chim. Technol. Vody,1994