@prefix skos:	<http://www.w3.org/2004/02/skos/core#> .
@prefix isac:	<http://webisa.webdatacommons.org/concept/> .
isac:_fm_	skos:broader	isac:angle_modulation_ .
isac:frequency_modulation_	skos:broader	isac:angle_modulation_ .
<http://webisa.webdatacommons.org/concept/phase+modulation_pm_>	skos:broader	isac:angle_modulation_ .