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 AcapB 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 TAcapBX/(TAcapBA+TAcapBB).
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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