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Philip R. Johnson, S L. Hulbert, R Klaffky, N B. Brookes, Andrew Clarke, B Sinkovic, N V. Smith, R J. Celotta, M H. Kelley, Daniel T. Pierce, M R. Scheinfein, B J. Waclawski, M R. Howells
The drive toward increased safety for coal miners has led to the development of computerassisted methods of underground coal mining. The development of control