Perkins, Michael R. <br/><br/>
Modal expressions in english 

. - London  : Frances Pinter, 1983
. - X-186 p.  ; 23 cm. 
 - Open linguistics series .
<br/><br/>Bibliogr.index 
<br/><br/><label>ISBN: </label>0861875141 0861872983 
<br/><br/><label>Source: </label> Don britannique 
<br/><br/><label>Universal Decimal Class. No.: </label>802.0