10 Julius Caesar implemented his calendar of 365 days with 366 every 4th year. 11 Khayyam invented an accurate 33-year solar calendar, the Jalali Calendar. 12 Lilius was principal author of the Gregorian Calendar. 13 Meton discovered that 235 lunar months almost equal 19 solar years. This program is free for personal use.
Permission is granted for non-commercial distribution.