Cita APA (7th ed.)

Brekke, A., & Egeland, A. (1994). The northern lights: Their heritage and science. Grndahl Dreyer.

Cita Chicago (17th ed.)

Brekke, Asgeir, i Alv Egeland. The Northern Lights: Their Heritage and Science. Oslo: Grndahl Dreyer, 1994.

Cita MLA (8th ed.)

Brekke, Asgeir, i Alv Egeland. The Northern Lights: Their Heritage and Science. Grndahl Dreyer, 1994.