Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MOMA_1972__76_177619, author = {K.E. Hirst}, title = {The {Length} of {Periodic} {Continued} {Fractions.}}, journal = {Monatshefte f\"ur Mathematik}, pages = {428--435}, publisher = {mathdoc}, volume = {76}, year = {1972}, zbl = {0245.10005}, url = {http://geodesic.mathdoc.fr/item/MOMA_1972__76_177619/} }
K.E. Hirst. The Length of Periodic Continued Fractions.. Monatshefte für Mathematik, Tome 76 (1972), pp. 428-435. http://geodesic.mathdoc.fr/item/MOMA_1972__76_177619/