Briggs, D. <br/><br/>
Plant variation and evolution  D. Briggs and S.M. Walters. 

 - 2nd ed. 
 - Cambridge  Cambridge University Press  1990 
 - xv, 412p., ill. 23cm. 
<br/><br/><label>ISBN: </label>0-521-45918. 
<br/><br/><label>Dewey Class. No.: </label>581,  / B83P