Warn , Chris  <br/><br/>
The ordnance survey map skills book :  

 - Nelson :   London ;  1980. 
 - 95 p ; 21 cm .  01 
 - 2024-10-22 
<br/><br/><label>ISBN: </label>0174342845 
<br/><br/><label>Nat. Bib. No.: </label>0010759 
<br/><br/><label>Nat. Bib. Agency Control No.: </label>WAR 
<br/><br/><label>Universal Decimal Class. No.: </label>930