Columbia subject headings:
Adult education--England--Portsmouth--History--Sources.
University extension--Great Britain--History--Sources.
University of Cambridge. Board of Extra-Mural Studies--History--Sources.
Harvard subject headings:
Adult education--England--Portsmouth--History--Sources.
University extension--England--Portsmouth--History--Sources.
Princeton subject headings:
Adult education--England--Portsmouth--History--Sources.
University extension--Great Britain--History--Sources.
University of Cambridge. Board of Extra-Mural Studies--History--Sources.