1. R. P. Feynman and A.R. Hibbs, Quantum mechanics and path integrals (McGraw Hill Book Co., New York etc., 1965), especially sec. 7–2.
2. K. Itô, in: Proc. 5th Berkeley symposium on mathematical statistics and probability, vol. II part I (Univ. California Press, Berkeley, 1966), p. 145.
3. J. Tarski, in: Complex analysis and its applications, vol. III (IAEA, Vienna, 1976), p. 193.
4. Lecture notes in physics;J Tarski,1979
5. E. Nelson, J. Math. Phys. 5, 332 (1964).