Let $X$ be a compact oriented manifold, and $A$ and $B$ closed oriented submanifolds intersecting cleanly. Then I've always been under the impression that pushing forward a cohomology class from $A$ to $X$ and then pulling back from $B$ should have a base change formula where instead one pulls back to $Acap B$ and pushes forward to $B$.
Of course, this couldn't possibly be right if $A$ and $B$ aren't transverse. I think in the non-transverse case, one should correct by the Euler class of the excess bundle $T_{Acap B}X/(T_{Acap B}A+T_{Acap B}B)$.
All of my intuition for algebraic topology tells that this true and easy to prove, but of course, one can't write that in a paper.
Does anyone know a convenient reference for this fact? I've tried to find it via Google, but apparently can't find the right keywords, and a quick scan of Hatcher came up negative.
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