1. Arens, R.: Dense inverse limit rings. Michigan Math. J.5, 169?182 (1958).
2. ?? The group of invertible elements of a commutative Banach algebra. Studia Math. (Seria Spec.) Z.1, 21?23 (1963).
3. ?? Weierstrass products for inverse limits of Banach algebras. Math. Ann.163, 155?160 (1966).
4. Dors, A. G.: On the spectrum of anF-algebra. Thesis, University of Utah, 1970.
5. Rickart, C. E.: General theory of Banach algebras. Princeton: Van Nostrand 1960.