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.
Diagram of entity types and related databases for identifier origin. Blue boxes show the different entity types; green boxes, primarily recommended databases and orange boxes, alternative databases (see also Supplementary File S3). Identifiers from specific databases are recommended for each entity type.
