The most influential work produced by al-Farghani was his textbook "Kitāb fī Jawāmiʿ ʿIlm al-Nujūm" ( "A Compendium of the Science of the Stars") or "Elements of astronomy on the celestial motions", written sometime between about 833 and 857. "Elements" was a descriptive summary of Ptolemy's Almagest that included the findings and revised values of earlier Islamic astronomers. Among the revisions included in the book were corrections to calculations of the circumference of the Earth, the Earth's axial tilt, and the apsides of the Sun and the Moon. Though al-Farghani's summary of Almagest contained these numerical corrections, the summary itself did not emphasize the mathematics of Ptolemy's astronomical theory and was instead focused more on conveying the conceptual parts of the theory in an easily-understood manner. Al-Farghani's book was translated into Latin in the 12th century by John of Seville in 1135 and later by Gerard of Cremona prior to 1175. These translations remained very popular in Europe until the time of Regiomontanus. Dante Alighieri's knowledge of Ptolemaic astronomy, which is evident in his "Divina Commedia" as well as other works such as the "Convivio", seems to have been drawn from his reading of Alfraganus. "Elements" was also translated into Hebrew by Jacob Anatoli sometime from 1231 to 1235. This translation of "Elements" contains an additional section discussing Ptolemy's 48 constellations, which was probably also written by al-Farghani, but is not found in other translations of the book. Drawing primarily from Anatoli's Hebrew translation, but also from John of Seville's previous Latin translation, Jacob Christmann translated yet another Latin translation of "Elements" in 1590. In the 17th century the Dutch orientalist Jacob Golius published the Arabic text on the basis of a manuscript he had acquired in the Near East, which was accompanied by the final recorded Latin translation and extensive notes and revisions.