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I thank Professor Boju Jiang for pointing out that Theorem 2.3 of [3] which is quoted as Lemma 1.2 of [1], is false in general. Consequently, without additional hypotheses, the main results in [1, §2] do not hold in the generality as stated. Let f, g : M1 → M2 be as in [1, 2.1]. In addition, we assume that M1, M2 are compact, M1 is triangulable and π1(M1) is finite so that the universal cover M1 is also compact. By a result of Schirmer, we may assume without loss of generality that the coincidence set of f and g is given by Cf,g = {x1, . . . , xk} such that each xi is a distinct coincidence class. It follows from [1, §1] that each root class of η : M1 → M2 must lie entirely inside the fiber p−1 1 (xi) over xi for some i. Following [2, Cor. 5], the root classes of η have the same root index. Furthermore, η has exactly |K| = |π1(M2)| root classes if deg η 6= 0. It is shown in the proof of [1, 2.1] that every point of p−1 1 (xi) has the same root index which coincides with the coincidence index at xi. By summing all the indices, we obtain deg η = L(f, g) · |π1(M1)|. C a s e (I): If K is infinite, then deg η = 0 and hence every xi is inessential. Thus N(f, g) = 0 and f and g are deformable to be coincidence free. C a s e (II): Suppose that K is finite. It follows that deg η = |K| · ω = L(f, g) · |π1(M1)| where ω is the root index of a root class of η. If L(f, g) = 0 then deg η = 0 and hence N(f, g) = 0. Again, f and g are deformable to be coincidence free. Let r = |π1(M2)|/|π1(M1)|. Now suppose that L(f, g) 6= 0.

Corrections to "On the computation of the Nielsen numbers and the converse of the Lefschetz coincidence theorem" (Fund. Math. 140 (1992), 191–196)