Brahma Nand & others  <br/><br/>
Spherical Harmonics  and Partial  differential  equations  8th ed 

 - 4 
 - Meerut  Kedar nath ram nath co. 
 - 167 
<br/><br/><br/>ENGLISH 
<br/><br/><label>Subjects--Facted Index Terms: </label><br/>spherical