Columbia subject headings:
Copyright--Royalties--United States.
Photocopying services in libraries--United States.
Photocopying--Fair use (Copyright)--United States.
Harvard subject headings:
Copyright--Royalties--United States.
Photocopying services in libraries--United States.
Photocopying--Fair use (Copyright)--United States.
Princeton subject headings:
Photocopying services in libraries--United States.
Photocopying--Fair use (Copyright)--United States.
Photocopying--Royalties--United States.