Inter Gravissimas Bill Spencer's (in English) translation of the Inter Gravissimas, 1999, revised 2002, based on Rodolphe Audette's transcription of the (in Latin) text. Also includes Rodolphe Audette's translation into (in French).
"Inter gravissimas" in Christoph Clavius, Romani calendarii a Gregorio XIII. P. M. restituti explicatio, 1603. (in Latin) The bull begins on page 53, counting from the front cover. The title page is p. 5.
nd.edu
mathematics.library.nd.edu
Opera Mathematica of Christoph ClaviusArchived 2012-05-08 at the Wayback Machine(in Latin) Go to Page, Go To Specific Page, Work: Roman Calendar of Gregory XIII, Page: Calendar – p. 13. The fifth volume contains his works on the Gregorian calendar.
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Opera Mathematica of Christoph ClaviusArchived 2012-05-08 at the Wayback Machine(in Latin) Go to Page, Go To Specific Page, Work: Roman Calendar of Gregory XIII, Page: Calendar – p. 13. The fifth volume contains his works on the Gregorian calendar.