@prefix skos:	<http://www.w3.org/2004/02/skos/core#> .
@prefix isac:	<http://webisa.webdatacommons.org/concept/> .
isac:_month_	skos:broader	isac:variable_component_ .
isac:_fuel_	skos:broader	isac:variable_component_ .
isac:_year_	skos:broader	isac:variable_component_ .