@prefix skos:	<http://www.w3.org/2004/02/skos/core#> .
@prefix isac:	<http://webisa.webdatacommons.org/concept/> .
isac:_glass_	skos:broader	isac:multiple_surface_ .
isac:_metal_	skos:broader	isac:multiple_surface_ .
isac:_marble_	skos:broader	isac:multiple_surface_ .
isac:_paper_	skos:broader	isac:multiple_surface_ .
isac:_grass_	skos:broader	isac:multiple_surface_ .
isac:_wood_	skos:broader	isac:multiple_surface_ .
isac:_dirt_	skos:broader	isac:multiple_surface_ .
isac:_tile_	skos:broader	isac:multiple_surface_ .
isac:_gravel_	skos:broader	isac:multiple_surface_ .
isac:_terrazzo_	skos:broader	isac:multiple_surface_ .