Columbia subject headings:
Nonprofit organizations--Law and legislation--United States.
Nonprofit organizations--United States--Handbooks, manuals, etc.
Nonprofit organizations--United States--Information services--Directories.
Harvard subject headings:
Nonprofit organizations--Law and legislation--United States
Nonprofit organizations--United States--Handbooks, manuals, etc.
Nonprofit organizations--United States--Information services--Directories.
Princeton subject headings: