<http://ns.inria.fr/covid19/PMC7120653#body_text>	<http://purl.org/dc/terms/subject>	"Smallpox vaccines" .
<http://ns.inria.fr/covid19/PMC7120653#body_text>	<http://purl.org/dc/terms/subject>	"Commercial-free television networks" .
<http://ns.inria.fr/covid19/PMC7120653#body_text>	<http://purl.org/dc/terms/subject>	"Areas of London" .