Columbia subject headings:
Information storage and retrieval systems--Directories.
Libraries--Automation--Directories.
Library science--Computer programs--Directories.
Microcomputers--Directories.
Harvard subject headings:
Information storage and retrieval systems--Directories.
Libraries--Automation--Directories.
Library science--Computer programs--Directories.
Microcomputers--Directories.
Princeton subject headings:
Information storage and retrieval systems--Directories.
Libraries--Automation--Directories.
Library science--Computer programs--Directories.
Microcomputers--Directories.