Activities relating to drinking water and wastewater services -- Guidelines for the assessment and for the improvement of the service to users— 74 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 management of drinking water utilities and for the assessment of drinking water services— 66 стр.
