Citazione Stile APA (7a Edizione)

Sommer, P., Heater, D., & Owen, G. (1978). Countries, continents and communities (1. publ., reprinted and updated.). Harrap.

Citazione stile Chigago Style (17a edizione)

Sommer, Peter, Derek Heater, e Gwyneth Owen. Countries, Continents and Communities. 1. publ., reprinted and updated. Walton-on-Thames, Surrey [u.a.]: Harrap, 1978.

Citatione MLA (9a ed.)

Sommer, Peter, et al. Countries, Continents and Communities. 1. publ., reprinted and updated. Harrap, 1978.