%0 Journal Article %A Eisenbrand, Friedrich %T Pope Gregory, the calendar, and continued fractions %J Documenta mathematica %D 2012 %P 87-93 %V Optimization Stories %I mathdoc %U http://geodesic.mathdoc.fr/item/DOCMA_2012__S3__a30/ %G en %F DOCMA_2012__S3__a30