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3. Sabra, A.: Ibn al-haytham, brief life of an arab mathematician: died circa 1040. Harvard Magazine, 54–55 (2003)
4. Sabra, A.: Ibn al-haytham’s criticisms of ptolemy’s optics. Journal of the History of Philolosophy 4, 145–149 (1966)
5. Berger, J., Mohr, J.: Another Way of Telling. Pantheon, New York (1982)