<http://ns.inria.fr/covid19/PMC7199361#body_text>	<http://purl.org/dc/terms/subject>	"Problem solving methods" .
<http://ns.inria.fr/covid19/PMC7199361#body_text>	<http://purl.org/dc/terms/subject>	"Nitrogen(\u22123) compounds" .
<http://ns.inria.fr/covid19/PMC7199361#body_text>	<http://purl.org/dc/terms/subject>	"Network theory" .