Columbia subject headings:
Conscientious objection--United States--History.
Conscientious objectors--United States--History.
Harvard subject headings:
Conscientious objection--United States--History.
Conscientious objectors--United States
Conscientious objectors--United States--History.
Princeton subject headings:
Conscientious objection--United States--History.
Conscientious objectors--United States--History.