Joan Bybee, Revere Perkins, and William Pagliuca <br/><br/>
The Evolution of Grammar  Tense, Aspect, and Modality in the Language of the World 

 - Chicago and London  The University of Chicago Press  1994 
<br/><br/><label>ISBN: </label>0-226-08665-8 
<br/><br/><label>Dewey Class. No.: </label>410BYBT