Swan upping   : annual swan marking on the Thames by the Vintners Company, the  Dyers Company and the Monarch's Swan Marker 

 -  2004. 
 - p. 8 :  
<br/><br/> Periodical article. 
<br/><br/><label>In:</label>  Essex folk news (EFN)  , 123 (June 2004), p. 8