Ecological stability 
<label>;</label> Usher, M. B. <label>;</label> Williamson, M.H. 
 - London  Chapman and Hall  1974 
 - xii, 196p.  24 cm. 
<br/><br/><label>ISBN: </label>0412126109 
<br/><br/><label>Dewey Class. No.: </label>574.5  / ECO