A cost comparison of selected coal mines from Australia, Canada, Colombia, South Africa, and the United States. 

 - [Washington, D.C.] :  United States Dept. of the Interior, Bureau of Mines,  1993. 
 - vi, 65 p. :  ill. 
 - Special publications. .
 - Special publication (United States. Bureau of Mines). .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Coal trade--Costs--Case studies.<br/>Coal mines and mining--Costs--Case studies.