@book{250417,
	author = {Wallis, W. D.. and George, J. C.},
	title = {Introduction to combinatorics /},
	publisher = {CRC Press, Taylor & Francis Group,},
	year = {[2017]},
	series = {Discrete mathematics and its applications},
	address = {Boca Raton :},
	edition = {Second edition.},
	note = {"A Chapman & Hall book."}
}