"Astronomie." . . "Sterrenkunde." . . "Mathematicians." . . "Astronomie de la Renaissance." . . . . . . . . "Three imperial mathematicians : Kepler trapped between Tycho Brahe and Ursus" . . "Biography" . "Biography"@en . . . . . . . . . . . . . . . . . "Three imperial mathematicians: Kepler trapped between Tycho Brahe and Ursus" . . . . . . . . . . . . . . . . "Three imperial mathematicians Kepler trapped between Tycho Brahe and Ursus"@en . "Three imperial mathematicians Kepler trapped between Tycho Brahe and Ursus" . "History" . . "History"@en . . . . . . . . "Astronomer." . . "Wiskunde." . . "Astronomers." . . "Allemagne." . . "Danemark." . . "S. XVI" . . "Astronomia Història." . . "Astronomy." . . "Histoire 16e siècle." . . . . "Astronomer Denmark Biography" . . "Astronomer Denmark Biography." . "Astronomy history." . . "Histoire 17e siècle." . .