Goldblatt, Robert <br/><br/>
Orthogonality and spacetime geometry 
Robert Goldblatt 
 - New York:  Springer-Verlag,  1987. 
 -  viii, 189p. 
<br/><br/> Includes bibliography and index 
<br/><br/><br/>eng 
<br/><br/><label>ISBN: </label>0-387-96519-X 
<br/><br/><label>Dewey Class. No.: </label>516.4  / GOO