1. E. A. Gorin, ?Commutative Banach algebras generated by a group of unitary elements,? Funktsional. Analiz i Ego Prilozhen.,3, 86?87 (1967).
2. K. de Leeuw and H. Mirkil, ?Rotation-invariant algebras on the n-sphere,? Duke Math. J.,30, No. 4, 667?672 (1963).
3. B. V. Shabat, Introduction to Complex Analysis [in Russian], Nauka (1969).
4. A. Browder and J. Wermer, ?Some algebras of functions on an arc,? J. Math. and Mech.,12, No. 1, 119?130 (1963).
5. E. Bishop, ?Uniform algebras,? Proc. Conf. Complex Analysis, Minneapolis (1964).