  It is well known that the classical diagram lemmas of homological algebra for
abelian groups can be generalized to non-abelian group-like structures, such as
groups, rings, algebras, loops, etc. In this paper we establish such a
generalization of the "salamander lemma" due to G. M. Bergman, in a self-dual
axiomatic context (developed originally by Z. Janelidze), which applies to all
usual non-abelian group-like structures and also covers axiomatic contexts such
as semi-abelian categories in the sense of G. Janelidze, L. Marki and W. Tholen
and exact categories in the sense of M. Grandis.
