Stars and sextants 1904. Star distance tables for facilitating the use of Lord Ellenborough's method of correcting the centring and total errors of sextants at sea /
Sprigge, John Abner.
Doak, Wm. Fraser,M.A., F.R.A.S.
Hudson, T. Charlton,B.A., F.R.A.S.
Cox, Arthur S.,B.Sc., A.R.C.Sc.
London, 
1903.