Langman, H.R. <br/><br/>
Electrical horology 

 - London  Crosby lockwood and son  1923 
 - xi,164 p. 
<br/><br/> Includes index 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Electrical horology
<br/><br/><label>Dewey Class. No.: </label>D66,8(MB9) F3L