TY - BOOK ED - German Society for Soil Mechanics and Foundation Engineering ED - International Congress on Rock Mechanics (September 16 - 20,1991) TI - Proceedings Seventh International Congress on Rock Mechanics, Zacatecas, Mexico, 16 - 20 1991 : Volume 3 SN - 9054100015X U1 - 624.131 19 PY - 1991/// CY - Rotterdam PB - A. A. Balkema KW - Rock mechanics KW - Congresses N1 - Proceedings 7th Congress on Rock Mechanics, September 16 - 20, 1991; Volume 3 : Opening and closing ceremony : General reports and additional contributions : Workshops : Annexes; Includes bibliographical references ER -