Impact of rock engineering on mining and tunnelling economics :
proceedings of the SANGFORM Symposium, Welkom, 7-8 October, 1991 /
International Society for Rock Mechanics, South African National Group.

APA Citation

South African National Group on Rock Mechanics., International Society for Rock Mechanics., SANGORM Symposium (1991 : Welkom, S. Africa). (1991). Impact of rock engineering on mining and tunnelling economics: proceedings of the SANGFORM Symposium, Welkom, 7-8 October, 1991. Orange Grove, South Africa: SANGFORM.

MLA Citation

South African National Group on Rock Mechanics, International Society for Rock Mechanics, and South Africa) SANGORM Symposium (1991 : Welkom. Impact of Rock Engineering On Mining And Tunnelling Economics: Proceedings of the SANGFORM Symposium, Welkom, 7-8 October, 1991. Orange Grove, South Africa: SANGFORM, 1991.