Columbia subject headings:
Libraries--Automation.
Library catalogs and users.
Machine-readable bibliographic data.
Online bibliographic searching.
Online library catalogs.
Harvard subject headings:
Libraries--Automation
Library catalogs and users.
Machine-readable bibliographic data.
Online bibliographic searching.
Online library catalogs.
Princeton subject headings:
Libraries--Automation.
Library catalogs and users.
Machine-readable bibliographic data.
Online bibliographic searching.
Online library catalogs.