Cita APA (7a ed.)

Ellis, S. G., Hálfdanarson, G., & Isaacs, A. K. (2006). Citizenship in historical perspective. Plus.

Cita Chicago Style (17a ed.)

Ellis, Steven G., Gudmundur Hálfdanarson, y Ann Katherine Isaacs. Citizenship in Historical Perspective. Pisa: Plus, 2006.

Cita MLA (9a ed.)

Ellis, Steven G., et al. Citizenship in Historical Perspective. Plus, 2006.