Abstract
For every module M we have a natural monomorphism \(\Psi :\coprod\limits_{i \in I} {{\text{Hom}}_R \left( {M,A_i } \right) \to {\text{Hom}}_R \left( {M,\coprod\limits_{i \in I} {A_i } } \right)} \)and we focus our attention on the case when Ψ is also an epimorphism. Some other colimits are also considered.
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Bashir, R.E., Kepka, T. & Němec, P. Modules Commuting (Via Hom) with Some Colimits. Czech Math J 53, 891–905 (2003). https://doi.org/10.1023/B:CMAJ.0000024528.13249.45
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DOI: https://doi.org/10.1023/B:CMAJ.0000024528.13249.45