The isomorphism problem for incidence rings (vol 187, 201, 1999)

In this note the authors correct and extend results presented in their article The Isomorphism problem for incidence rings, Pacific J. Math., 187(2) (1999), 201-214. Specifically, it is shown that for a large class of rings (including those with finite right Goldie dimension, semilocal, and many commutative rings), if P and P' are finite preordered sets for which there is an isomorphism of incidence rings I (P, R) similar or equal to I (P', R), then P similar or equal to P'.