Figure 2.
The 3 types, 9 groups, and 27 subgroups of the AO/OTA classification. Reprinted from. Marsh 2007 [14] with permission from JOT, Copyright Clearance Center.
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.