Negro, A., & Ferreira, A. A. (1998). Tunnels and metropolises: : proceedings of the World Tunnel Congress'98 on Tunnels and Metropolises, Sao Paulo, Brazil, 25-30 April 1998. Rotterdam: A. A. Balkema.
Παραπομπή Chicago StyleNegro, Arsenio, and Agrimiro A. Ferreira. Tunnels and Metropolises: : Proceedings of the World Tunnel Congress'98 On Tunnels and Metropolises, Sao Paulo, Brazil, 25-30 April 1998. Rotterdam: A. A. Balkema, 1998.
Παραπομπή MLANegro, Arsenio, and Agrimiro A. Ferreira. Tunnels and Metropolises: : Proceedings of the World Tunnel Congress'98 On Tunnels and Metropolises, Sao Paulo, Brazil, 25-30 April 1998. Rotterdam: A. A. Balkema, 1998.
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