Water quality; determination of total arsenic; silver diethyldithiocarbamate spectrophotometric method (ISO 6595:1982); german version EN 26595:1992— 12 стр.
Products used for treatment of water intended for human consumption - Inorganic supporting and filtering materials - Methods of test; German version EN 12902:1999— 22 стр.
Methods of soil investigations for agricultural engineering - Chemical laboratory tests - Part 10: Testing and evaluation of water for irrigation— 11 стр.