1. L. Fuchs
Abelian groups, Budapest, Publishing House of the Hungarian Academy of Sciences, 1958.
2. Paul R. Halmos
Measure theory, New York, D. Van Nostrand Co., 1950.
3. Edwin Hewitt
The asymmetry of certain algebras of Fourier-Stieltjes transforms, Michigan Math. J., vol. 5 (1958), pp. 149–158.
4. Edwin Hewitt and H. S. Zuckerman
A group-theoretic method in approximation theory, Ann. of Math. (2), vol. 52 (1950), pp. 557–567.
5. John L. Kelley
General topology, New York, D. Van Nostrand Co., 1955.