Classification
UPN - Water protection, water quality, clean water
UPK - Water resources, water supply
6
UPCE - Water chemistry
5
UPT - Water pollution control and measurement
4
UPP - Water pollution
3
GTA - Hydrology - general
2
UPC - Water - general aspects
2
USN - Waste water treatment
2
CHRV - Water and its properties
1
GMAB - Hydrogeochemistry
1
UCE - Environmental impact, environmental pollution
1
UPA - Water - handbooks
1
UPTF - Organic pollutants in water
1
UPTK - Volatile pollutants in water
1
UPTN - Inorganic pollutants in water
1
UPVC - Groundwater
1
UPVF - Surface waters - streams, rivers, lakes
1
UPW - Drinking water
1
YEC - Law on waters
1