@book {Sokal1963Freeman,
	title = {{Principles of Numerical Taxonomy}},
	year = {1963},
	pages = {359},
	publisher = {W.~H. Freeman and Company},
	organization = {W.~H. Freeman and Company},
	address = {San Francisco},
	author = {Sokal, R.~R. and Sneath, P.~H.~A.}
}