id	keyword
gc-106	groundwater levels
gc-106	drava
gc-106	precipitation
gc-106	aquifer
gc-106	trend
gc-106	river
gc-106	sava
gc-106	zagreb
gc-106	area
gc-106	period
gc-106	fig
gc-106	drava river
gc-106	ned
gc-106	quantities
gc-106	croatia
gc-106	piezometers