Poribesh arthabigyan. 
By Rafique Ahmed. 
 - 4th. 
 - Jorhat.:  Unika prakashan.,  2008. 
 - 340 p.:  24 cm. 
<br/><br/><label>Subjects--Index Terms: </label>Environmental science. 
<br/><br/><label>Dewey Class. No.: </label>333.7