Columbia subject headings:
Information services--Periodicals.
Information storage and retrieval systems--Periodicals.
Machine-readable bibliographic data--Periodicals.
Harvard subject headings:
Information services--Periodicals.
Information storage and retrieval systems--Periodicals
Machine-readable bibliographic data--Periodicals.
Princeton subject headings:
Information services--Periodicals.
Information storage and retrieval systems--Periodicals.
Machine-readable bibliographic data--Periodicals.
Periodicals.