@book{17612,
	author = {Nand, Brahma},
	title = {Spherical Harmonics and partial differential equations : complete theory and all examples fully solved for post graduateclasses},
	publisher = {Kedar Nath and Ram Nath,},
	year = {1968},
	address = {Meerut :},
	edition = {4th rev. ed.}
}