1. 1) Wilgram, G. F. et al.: Arch. Derm. 94: 127, 1966.
2. 2) Ishibashi, Y. et al.: Arch. Klin. Exp. Derm. 232: 205, 1968.
3. 3) Ishibashi, Y. et al.: ibid. 233: 11, 1968.
4. 4) Ishibashi, Y. et al.: ibid. 233: 124, 1968.
5. 5) Hirone, T.: Electron Microscopy. 18: 63, 1969.