@book{4172,
	author = {Das, B. C. and Mukherjee, B. N.},
	title = {Differential calculus /},
	publisher = {U.N. Dhur & Sons.Private Ltd.,},
	year = {c1979 [Reprinted 2005].},
	address = {Calcutta :},
	edition = {43rd ed.}
}