PLOS Thesaurus	Material Natural Resource	Source
http://sweet.jpl.nasa.gov/2.3/matrNaturalResource.owl#CrudeOil	http://localhost/plosthes.2017-1#53	LOOM
http://sweet.jpl.nasa.gov/2.3/matrNaturalResource.owl#NaturalGas	http://localhost/plosthes.2017-1#1275	LOOM
http://sweet.jpl.nasa.gov/2.3/matrNaturalResource.owl#Petroleum	http://localhost/plosthes.2017-1#898	LOOM
http://sweet.jpl.nasa.gov/2.3/matrNaturalResource.owl#Coal	http://localhost/plosthes.2017-1#3361	LOOM