@prefix skos:	<http://www.w3.org/2004/02/skos/core#> .
@prefix isac:	<http://webisa.webdatacommons.org/concept/> .
isac:mountaintop_removal_	skos:broader	isac:mining_method_ .
isac:strip_mining_	skos:broader	isac:mining_method_ .