International Institute for Aerospace Survey and Earth Sciences  <br/><br/>
The basic principles of multi coloure map making  Audio visual learning package 

 - Irrigation Department  Colombo 
 - 5p. 
<br/><br/><label>Nat. Bib. No.: </label>6892 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Multi colour map
<br/><br/><label>Universal Decimal Class. No.: </label>528.923  / MEL