"The golden rectangle is a geometric figure which contains within it a scale of relationships. Celebrated by the ancient Greeks, the golden mean was probably not used widely in Renaissance architecture, but gained popularity in the twentieth century by Modernist and Beaux-Arts architects alike. The golden rectangle can be subdivided into a square and another smaller golden rectangle. The relationship between the length and width of the rectangle is governed by the golden mean." Gargus, 341
Source
Gargus, J. (1994). Ideas of Order: A Formal Approach to Architecture. Dubuque, Iowa: Kendall/Hunt Pub. Co. p. 341-342.