APA (7th ed.) Citation

Portland House (Firm). (1986). The New illustrated encyclopedia of knowledge (Rev. ed.). Portland House.

Chicago Style (17th ed.) Citation

Portland House (Firm). The New Illustrated Encyclopedia of Knowledge. Rev. ed. New York: Portland House, 1986.

MLA (9th ed.) Citation

Portland House (Firm). The New Illustrated Encyclopedia of Knowledge. Rev. ed. Portland House, 1986.