Europa Publications & Europa Publications. (1987). The world of learning 1987 (37. ed.). Staples Printers Rochester.
Chicago Style (17th ed.) CitationEuropa Publications and Europa Publications. The World of Learning 1987. 37. ed. Rochester: Staples Printers Rochester, 1987.
MLA (9th ed.) CitationEuropa Publications and Europa Publications. The World of Learning 1987. 37. ed. Staples Printers Rochester, 1987.