Παραπομπή APA

Maidl, B. (2008). Hardrock tunnel boring machines. Ernst and sohn.

Παραπομπή Chicago Style

Maidl, Bernhard...[et.al]. Hardrock Tunnel Boring Machines. Berlin: Ernst and sohn, 2008.

Παραπομπή MLA

Maidl, Bernhard...[et.al]. Hardrock Tunnel Boring Machines. Ernst and sohn, 2008.