Bellsystem Technical Jr. Nos 1-6 

 - New York  Ame. Telephone And Telagrapha  Co.  1962 
<br/><br/><label>Subjects--Topical Terms: </label><br/>D66m73:N22
<br/><br/><label>Dewey Class. No.: </label>D66m73:N22  / F2.41