_:b20513	<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>	<http://www.ontology-of-units-of-measure.org/resource/om-2/gigayear> .
_:b20777	<http://www.w3.org/1999/02/22-rdf-syntax-ns#rest>	_:b20513 .
_:b20513	<http://www.w3.org/1999/02/22-rdf-syntax-ns#rest>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#nil> .
_:b20777	<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>	<http://www.ontology-of-units-of-measure.org/resource/om-2/year-Tropical> .