Parkinson, Howard E. <br/><br/>
Mine pager to  public telephone interconnect system / 
by Howard E. Parkinson. 
 - [Washington] :  U.S. Dept. of the Interior, Bureau of Mines,  [1974]. 
 - 14 p. :  ill. 
 - Report of investigations ;  7976 .
 - United States.  Bureau of Mines.  Report of investigations ;  7976 .
 - Report of investigations (United States. Bureau of Mines) ;  7976 .
<br/><br/><label>LCCN: </label>91055141     
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone in mining.<br/>Mine communications systems.