In 1942, McCoy proved the following theorem:Let R be a commutative ring with multiplicative unit, and let f(x) be a
zero divisor in the
polynomial ring R[x]. Then there is a nonzero element r ∈ R with f(x)r = 0. In 1997 Mangesh B. Rege and Sima Chhawchharia introduced definitions of rings, which in 2006, independently and motivated by McCoy's 1942 theorem, were re-introduced by Pace P. Nielsen, who gave the concepts the names "right McCoy ring", "left McCoy ring", and "McCoy ring" (a ring which is both right McCoy and left McCoy). ==
Rings and Ideals (1948)==