Activities relating to drinking water and wastewater services -- Guidelines for the management of drinking water utilities and for the assessment of drinking water services— 66 стр.
Activities relating to drinking water and wastewater services -- Guidelines for the management of wastewater utilities and for the assessment of wastewater services— 70 стр.
Activities relating to drinking water and wastewater services -- Guidelines for the assessment and for the improvement of the service to users— 74 стр.
Plastics -- Symbols and abbreviated terms -- Part 1: Basic polymers and their special characteristics -- Amendment 1: New symbol ST for syndiotactic— 6 стр.