1. AGATSTON, S. A. (1939). Amer. J. Ophthal., 22, 420.
2. ANCKE, R. (1885). Zbl. prakt. Augenheilk., 9, 167.
3. 593. Abstract in Zbl. ges;BAKKER, C.;Geneesk. Tijdschr. Ned. Ind,1925
4. BARRETT, J. W. (1898). Intercolon. med. J. Aust., 3, 343.
5. BAUMEISTER, E. (1873). Graefes Arch. Ophthal., 19, Pt. 2, 261.