“A book containing lists of names of residents, organizations or business houses in a town, a group of towns or a country, in alphabetical order, and/or in order of situation in reads, or of firms in trade classifications arranged in alphabetical order; or of professional people, manufacturers or business houses in a particular tread or profession”. Harrods Librarian Glossary and Reference Book.
- World directory of mathematicians, 4th ed. Stockholm, Almqvist & Wiksell, 1970.
- World guide to technical information and documentation services, UNESCO, 1975.
- World of learning, 1947-, London, Europa, 1947-, Annual.