@prefix skos:	<http://www.w3.org/2004/02/skos/core#> .
@prefix isac:	<http://webisa.webdatacommons.org/concept/> .
isac:_subtraction_	skos:broader	isac:basic_arithmetic_ .
isac:_and_	skos:broader	isac:basic_arithmetic_ .
isac:_number_	skos:broader	isac:basic_arithmetic_ .
isac:_addition_	skos:broader	isac:basic_arithmetic_ .
isac:_fraction_	skos:broader	isac:basic_arithmetic_ .