Abu al-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani (lat: Alfraganus);Astronomer at the court of the Abbasid Caliphate in Baghdad.Farg'ona (Uzbekistan) around 800 - Egypt around 870.Works: Treatise on the astrolabe (9th century; complete title: al-Kitab al-Kamil fi Sana'at al-Asturlab al-Shimali wa-l-Janubi wa-'Ilaliha bi-l-Handasa wal-Hisab - The Complete Book on the Construction of Northern and Southern Astrolabes and their underlying principles by geometry and calculation).- Double page with text and illustration. -Fragment (parts 3-7; 72 leaves) of a manuscript.Egypt; Syria or Mesopotamia; c. 12th century.Black and red ink on paper; c. 24 x 15.6 cm.Scribe: Ibrahim ibn 鈥楢bd al Mun'im ibn Abi Muhammad ibn Nasr ibn Muqallid al-Ansari.London; Sotheby's;April 29; 1998; lot 37.