参考文献

Barkley Rosser, Explicit Bounds for Some Functions of Prime Numbers, American Journal of Mathematics 63 (1), 1941, pp. 211-232
J. Barkley Rosser, Lowell Schoenfeld, Sharper Bounds for the Chebyshev Functions θ(x) and ψ(x), Mathematics of Computation 29 (129), 1975, pp. 243-269
Lowell Schoenfeld, Sharper Bounds for the Chebyshev Functions θ(x) and ψ(x). II, Mathematics of Computation 30 (134), 1976, pp. 337-360