PubMed:32094225 / 1168-1172
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T185","span":{"begin":0,"end":4},"obj":"RB"}],"text":"Once"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok201","span":{"begin":0,"end":4},"obj":"RB"}],"text":"Once"}