Hobbs, Richard R. <br/><br/>
Marine navigation :  piloting and celestial and electronic navigation / 
Richard R. Hobbs. 
 - fourth edition. 
 - xvi, 677 pages. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>1-55750-381-8 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Navigation.<br/>Pilots and pilotage.<br/>Nautical astronomy.