Abstract
A modification is suggested for a 1934 example of Reinhold Baer which shows that not all homomorphisms $C\to(\operatorname{Aut} A)/(\operatorname{Inn}\space A)$ arise from conjugation action in group extensions $1\to A\to B\to C\to 1.$
Citation
L. G. Kovács. "A non-extendable abstract kernel." Illinois J. Math. 47 (1-2) 327 - 328, Spring/Summer 2003. https://doi.org/10.1215/ijm/1258488158
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