Παραπομπή APA

Halbertsma H. (2016). Colon classification (6.). ESS ESS publication.

Παραπομπή Chicago Style

Halbertsma H. Colon Classification. 6. New Delhi: ESS ESS publication, 2016.

Παραπομπή MLA

Halbertsma H. Colon Classification. 6. ESS ESS publication, 2016.