1. A1967-70 Tables for Assured Lives (1975). Institute of Actuaries, London; Faculty of Actuaries, Edinburgh
2. Abramowitz , M. Stegun , I. A. (1965). Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables , National Bureau of Standards, Applied Mathematics Series 55, Fourth Printing, U. S. Government Printing Office, Washington, D.C
3. Six-term formulas for routine actuarial interpolation.;Beers;Record Amer. Inst. Actuaries,1944