Παραπομπή APA

Brekke, T. L., & Jorstad, F. A. (1970). Large permanent underground openings: Proceedings of the international symposium held in Oslo 23-25 September 1969. Oslo: Universitetsforlaget.

Παραπομπή Chicago Style

Brekke, Tor L., and Finn A. Jorstad. Large Permanent Underground Openings: Proceedings of the International Symposium Held in Oslo 23-25 September 1969. Oslo: Universitetsforlaget, 1970.

Παραπομπή MLA

Brekke, Tor L., and Finn A. Jorstad. Large Permanent Underground Openings: Proceedings of the International Symposium Held in Oslo 23-25 September 1969. Oslo: Universitetsforlaget, 1970.

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