1. Bunin, A. Y.: Scientific Notes Helmholtz Ophthal. Inst. 10, 138–143 (1965)
2. Bunin, A. Y.: Ophthal. Lit. 19, 711 (1965).
3. Giannini, D.: Ann. Ottal. 62, 262–284 (1934).
4. Gradle, H. S.: J. Amer. Med. Ass. 115, 495–496 (1940).
5. Rones, B.: Amer. J. Ophthal. 41, 408–419 (1956).