PubMed:32134681 / 2715-2726
Annnotations
LitCovid-PAS-Enju
{"project":"LitCovid-PAS-Enju","denotations":[{"id":"EnjuParser_T540","span":{"begin":0,"end":11},"obj":"NNS"}],"text":"frequencies"}
LitCovid-TimeML
{"project":"LitCovid-TimeML","denotations":[{"id":"tok641","span":{"begin":0,"end":11},"obj":"NNS"}],"text":"frequencies"}