1. The law of anomalous numbers;Benford,1938
2. P. Diaconis, Limits of measures of the integers with application to random number generators and the distribution of leading digits, Memorandum NS-211, Department of Statistics, Harvard University.
3. On the probability that a random integer has initial digit A;Flehinger;Amer. Math. Monthly,1966
4. On the distribution of numbers;Hamming;Bell System Tech. J.,1970