## A pullback theorem for cofibrations.(English)Zbl 0617.55002

The pullback theorem in this note is an extension of a well-known theorem of A. Strøm which states: if $$p: E\to B$$ is a fibration and $$A\subset B$$ is a closed cofibration, then $$p^{-1}(A)\subset E$$ is a closed cofibration. An application on locally equiconnected spaces, and a discussion of the dual problem are also given.

### MSC:

 55P05 Homotopy extension properties, cofibrations in algebraic topology 55R05 Fiber spaces in algebraic topology 54F99 Special properties of topological spaces
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### References:

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