1. Lukacs, E., Characteristic Functions, Second Edition, 1970, Hafner, New York.
2. Marchaud, A., "Sur des derivées et sur les différences des fonctions de variable réeles," Journal de Mathematiques Pures et Appliquées, 1927, V. 6, 337–425.
3. Brown, B. M., "Characteristic functions, moments, and the central limit theorem," Annals of Mathematical Statistics, 1970, V. 41, 658–664.
4. Wolfe, S. J., "On the local behavior of characteristic functions," Annals of Probability, 1973, V. 1, 862–866.
5. Feller, W., An Introduction to Probability Theory and its Applications, V. 2, Second Edition, 1971, John Wiley, New York.