Elizabeth Eisenstein, The Printing Press as an Agent of Change (Cambridge, U.K.: Cambridge University Press, 1980), стр. 46.
158
Louis Karpinski, The History of Arithmetic (New York: Russell and Russell, 1965), стр. 68–71; Philip Gaskell, A New Introduction to Bibliography (Oxford, U.K.: Clarendon Press, 1972), стр. 251–265.
