00550nam a2200157Ia 4500 190328s9999||||xx |||||||||||||| ||und|| 62-8178 NITIL NITIL 21st 338.272 C555E Christenson, C L Economic redevelopment in bituminous coal the special case of technological advance in United States coal mines, 1930-1960 C L Christenson Cambridge Harvard University Press 1962 xxi, 312p. Bituminous Coal; Bitminous Coal industry BKS 15758 15758 0 0 DDC 0 0 NITIL NITIL 2019-04-02 0 338.272 C555E 38046 2019-04-02 00:00:00 2019-04-02 BKS