Παραπομπή APA

Alten, T. (1999). Challenges for the 21st century: Proceedings of the World Tunnel Congress '99, Oslo, Norway, 31 May-3 June 1999. Rotterdam: A.A. Balkema.

Παραπομπή Chicago Style

Alten, T.. Challenges for the 21st Century: Proceedings of the World Tunnel Congress '99, Oslo, Norway, 31 May-3 June 1999. Rotterdam: A.A. Balkema, 1999.

Παραπομπή MLA

Alten, T.. Challenges for the 21st Century: Proceedings of the World Tunnel Congress '99, Oslo, Norway, 31 May-3 June 1999. Rotterdam: A.A. Balkema, 1999.

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