<http://ns.inria.fr/covid19/PMC6263165#body_text>	<http://purl.org/dc/terms/subject>	"2017 regional elections in Spain" .
<http://ns.inria.fr/covid19/PMC6263165#body_text>	<http://purl.org/dc/terms/subject>	"Smallpox vaccines" .
<http://ns.inria.fr/covid19/PMC6263165#body_text>	<http://purl.org/dc/terms/subject>	"Hospitals established in 1869" .