<http://ns.inria.fr/covid19/PMC4358806#body_text>	<http://purl.org/dc/terms/subject>	"April observances" .
<http://ns.inria.fr/covid19/PMC4358806#body_text>	<http://purl.org/dc/terms/subject>	"Military association football clubs in North Korea" .
<http://ns.inria.fr/covid19/PMC4358806#body_text>	<http://purl.org/dc/terms/subject>	"Smallpox vaccines" .