1. An extensive list of references to the literature up to 1965 is given byR. Hilsch andG. v. Minnigerode: Basic problems in thin film physics, p. 521. Edited byR. Niedermayer andH. Mayer. Göttingen: Vandenhoeck and Ruprecht 1966.
2. Fischer, G., andR. Klein: Phys. Letters23, 311 (1966).
3. Saint-James, D., andP. G. de Gennes: Phys. Letters7, 306 (1963).
4. Klein, R., andG. Fischer: Phys. Rev.150, 222 (1966).
5. Deutscher, G., andP. G. de Gennes: To be published in Superconductivity. Edited byR. Parks.