Ross, Alf,  1899- <br/><br/>
Directives and norms / 
by Alf Ross 
 - London :  Routledge & Kegan Paul,  c1968 
 - ix, 188, 11 p. ;  22 cm. 
 - International library of philosophy and scientific method .
<br/><br/> Includes index 
<br/><br/><label>ISBN: </label>0710036353 :  PND 4.00 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Semantics (Philosophy)<br/>Logic<br/>Law--Philosophy
<br/><br/><label>Dewey Class. No.: </label>149.9