Tolkien, John Ronald Reuel, 1892-1973
The Lord of the rings
Houghton Miffiln, 1987
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Szasz, F.A.
Radicals of rings
John Wiley & Sons, 1981
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Anick, David
Differential algebras in topology
AK Peters 1993, 1993
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Passman, Donald S.
The algebraic structure of group rings
John Wiley & Sons, 1979
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Cohn, P.M.
Free rings and their relations
Academic Press, 1985
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