Ek, J.A. Van.  <br/><br/>
Threshold Level English :  Modern Languages Project   English 
Ek, J  Van and Alexander, L.G. 
 - New York :  Pergamon Press,  1975. 
 - xi, 253 p.:  ill.;  25 cm. 
<br/><br/><label>ISBN: </label>0080245889 
<br/><br/><label>Dewey Class. No.: </label>428.2  / EK