| Name | Info | Provider | Link |
|---|---|---|---|
| COVID-19 (Coronavirus Disease 2019) | free resource | MedlinePlus Health Information | https://medlineplus.gov/covid19coronavirusdisease2019.html |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=34304208.ui | |
| free resource | PubMed Central | https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/34304208/ | |
| free resource | Europe PubMed Central | https://europepmc.org/abstract/MED/34304208 | |
| free resource | Wolters Kluwer | https://doi.org/10.4103/ijo.IJO_1491_21 |