Columbia subject headings:
Communism--United States--1917-
Communism--United States.
Communist Party of the United States of America.
Governmental investigations--United States.
Harvard subject headings:
Communism--United States--1917-
Communist Party of the United States of America.
Governmental investigations--United States
Princeton subject headings:
Communism--United States--1917-.
Communist Party of the United States of America.
Governmental investigations--United States.