Ehlers, J. (ed.) <br/><br/>
Lecture notes in physics- 59 

 - Berlin  Springer-Verlag  1976 
 - vii,459p. 
<br/><br/> June 28 - July 2, 1976  
<br/><br/><label>ISBN: </label>354008004X 
<br/><br/><label>Dewey Class. No.: </label>530  / L39