APA-referens (7:e uppl.)

Saylor, R. B. (1949). An economic survey of Northumberland County, Pennsylvania. [s.n.].

Chicago-referens (17:e uppl.)

Saylor, Roger B. An Economic Survey of Northumberland County, Pennsylvania. State College, Pa.: [s.n.], 1949.

MLA-referens (8:e uppl.)

Saylor, Roger B. An Economic Survey of Northumberland County, Pennsylvania. [s.n.], 1949.