1. Lenin, PSS XXIX, p.131.
2. Cf. Wetter 1964 and Grujić 1969.
3. Peperzak 1989, p.19.
4. Cf. Geldsetzer 1968; for a general survey of positions, see Hösle 1984, pp.22–43; for an introduction to the problems involved: Schneider 1988.
5. Cf. Gouhier 19482, E. Castelli 1956, Braun 1973 and 1985, Guéroult 1984–1988 and 1979, Ehrhardt 1967, Hösle 1984, Schneider 1990 and 1992, Copleston 1979, Rorty 1984, Holland 1985, Peperzak 1981, Lavine 1989, Gracia 1992, and Holz 1992.