Chugh, C. P., Steele, K., Sharma, V. M., & Steele, K. (1996). Design criteria for drill rigs: Equipment and drilling techniques. Rotterdam: Balkema.
Παραπομπή Chicago StyleChugh, C. P., Ken Steele, V. M. Sharma, and Ken Steele. Design Criteria for Drill Rigs: Equipment and Drilling Techniques. Rotterdam: Balkema, 1996.
Παραπομπή MLAChugh, C. P., Ken Steele, V. M. Sharma, and Ken Steele. Design Criteria for Drill Rigs: Equipment and Drilling Techniques. Rotterdam: Balkema, 1996.
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