Conway, J. H. and Guy, R. K. "Three Greek Problems." In The
Book of Numbers. New York: Springer-Verlag, pp. 192-194, 1996.Lang,
S. and Trotter, H. "Continued Fractions for Some Algebraic Numbers." J.
reine angew. Math.255, 112-134, 1972.Sloane, N. J. A.
Sequences A002580/M1354 and A002945/M2220
in "The On-Line Encyclopedia of Integer Sequences."Uhler,
H. S. "Many-Figure Approximations For , , , and with Data." Scripta Math.18, 173-176, 1952.Wells,
D. The
Penguin Dictionary of Curious and Interesting Numbers. Middlesex, England:
Penguin Books, pp. 33-34, 1986.