PubMed:31995857 / 922-928
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T154","span":{"begin":0,"end":6},"obj":"IN"}],"text":"before"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok166","span":{"begin":0,"end":6},"obj":"IN"}],"text":"before"}