Hustrulid, W. A., Johnson, G. A., Hustrulid, W., & Johnson, G. A. (1990). Rock mechanics contributions and challenges: Proceedings of the 31st U.S. symposium: Colorado School of Mines, Golden, 18-20 June 1990. Rotterdam: Balkema.
Παραπομπή Chicago StyleHustrulid, W. A., G. A. Johnson, William Hustrulid, and G. A. Johnson. Rock Mechanics Contributions and Challenges: Proceedings of the 31st U.S. Symposium: Colorado School of Mines, Golden, 18-20 June 1990. Rotterdam: Balkema, 1990.
Παραπομπή MLAHustrulid, W. A., G. A. Johnson, William Hustrulid, and G. A. Johnson. Rock Mechanics Contributions and Challenges: Proceedings of the 31st U.S. Symposium: Colorado School of Mines, Golden, 18-20 June 1990. Rotterdam: Balkema, 1990.
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