HU Ji-ping.A case study of modern underground mining methods (IV):sublevel open stoping with draw points on footwall [J].Foreign Metal Mining Magazine,1990(9):40-43.是什么意思_HU Ji-ping.A case study of modern underground mining methods (IV):sublevel open stoping with draw points on footwall [J].Foreign Metal Mining Magazine,1990(9):40-43.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句