Sentman, Everette Edgar, Ed., et al. <br/><br/>
American educator encyclopedia, Vol.4: D-E-F 

 -  United Educators Inc. Publishers, New York  1961 
 - 1428 
<br/><br/><label>Subjects--Topical Terms: </label><br/>General encyclopedic works-American
<br/><br/><label>Dewey Class. No.: </label>R 031  SEN-A.04