1. Axenfeld, T., and Schuirenberg, E. (1901). Klin. Mbl. Augenheilk, 39, 64.
2. Bielschowsky, A. (1903). Ibid., 40, 308.
3. Bielschowsky, A. (1929). Gra?fes Arch. Ophthal., 121, 659.
4. Lectures on Motor Anomalies of the Eyes, Reprinted from Arch;Bielschowsky, A.;Ophthal. Amer. med. Ass. Chicago,1935
5. Fuchs, E. (1893). Beitr. Augenheilk, 11, 12.