PubMed:32061066 / 2008-2013
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T395","span":{"begin":0,"end":5},"obj":"NN"}],"text":"study"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok451","span":{"begin":0,"end":5},"obj":"NN"}],"text":"study"}