Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Distribution of institutions focused on COVID-19. (A) Bibliometric analysis of citations by the institution. Different colors indicate different clusters, and the size of circles reveals the number of publications. (B) Density map of institutions.
