GPO is the federal government’s primary centralized resource for gathering, cataloging, producing, providing, authenticating, and preserving published information in all its forms.
GPO is responsible for the production and distribution of information products and services for all three branches of the federal government.
Additionally, from The WPA Guide to Washington D.C. (1942):
Building No. 1...built in 1901, is an ornate red-brick structure eight stories high...