Durell, C.V. . <br/><br/>
Key to Advanced Trigonometry /  Textual Documents 
C.V.Durell & A.Robson. 
 - 1st ed. / 
 - London :  G Bell & Sons ,  1930. 
 - 380p. :  ill ;  18cm . 
<br/><br/><label>Subjects--Index Terms: </label>Trigonometry G-Mathematics 
<br/><br/><label>Dewey Class. No.: </label>514  / D 933 K