Ingham, A. E. (1937). “On the difference between consecutive primes”. Quarterly Journal of Mathematics Oxford8 (1): 255–266. doi:10.1093/qmath/os-8.1.255.
Baker, R. C.; Harman, G.; Pintz, G.; Pintz, J. (2001). “The difference between consecutive primes, II”. Proceedings of the London Mathematical Society83 (3): 532–562. doi:10.1112/plms/83.3.532.