Kieuskara
Jacobsen, William H. Jr. (1999): "Basque Language Origin Theories" In Basque Cultural Studies, edited by William A. Douglass, Carmelo Urza, Linda White, and Joseba Zulaika, 27–43. Basque Studies Program Occasional Papers Series, No. 5. Reno: Basque Studies Program, University of Nevada, Reno.