Cita APA (7th ed.)

Castle, G. H. (1993). Profiting from a geographic information system. GIS World.

Cita Chicago (17th ed.)

Castle, Gilbert H. Profiting from a Geographic Information System. Ft. Collins, Colo: GIS World, 1993.

Cita MLA (9th ed.)

Castle, Gilbert H. Profiting from a Geographic Information System. GIS World, 1993.