Cowan, Henry J. <br/><br/>
Environmental systems / 
Henry J. Cowan. 
 - New York :  Van Nostrand Reihold Company,  1983. 
 - 240 p. :  ill. ;  24 cm. 
<br/><br/><label>ISBN: </label>0442214901 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Cities and towns--Mathematical models.