A compendium of official notes and usage 

 - Bangkok :  The Department,  2001 
 - 270 
<br/><br/><label>ISBN: </label>9747774623 
<br/><br/><label>Subjects--Topical Terms: </label><br/>GOVERNMENT CORRESPONDENCE--THAILAND<br/>LETTER WRITING
<br/><br/><label>LC Class. No.: </label>JQ1745 .A55C57  / T424C