Europa Publications & Europa Publications. (1978). The world of learning 1977-78 (28. ed.). Staples Printers Rochester.
Chicago Style (17th ed.) CitationEuropa Publications and Europa Publications. The World of Learning 1977-78. 28. ed. Rochester: Staples Printers Rochester, 1978.
MLA (9th ed.) CitationEuropa Publications and Europa Publications. The World of Learning 1977-78. 28. ed. Staples Printers Rochester, 1978.