Talk:Continued fraction

The author of the bib entry [X] (former [7]) here is unclear. One has to check with the paper version of the Encycl. Same for old bib [6] (which has no reference in the text).

Ref [X] is presumably a work entitled "Die Quadratur des Kreises" (Squaring the circle). One possibility is a paper by E. Gumbel in Das Neue Tage-Buch. However there are several possible more modern references for the work of Lambert in 1768 and Legendre in 1794 on the continued fraction for tan(x) and its irrationality for rational x: for example,"Analysis by Its History" by Ernst Hairer, Gerhard Wanner (Springer, 2008) ISBN 0387770313. Richard Pinch (talk) 19:18, 4 September 2013 (CEST)