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I am reading about Chow groups and algebraic K-theory of schemes. I get to know that for smooth schemes the re is a strongly convergent spectral sequence $$E_2^{p,q} = CH^{-q}(X,-p-q) \implies K_{-p-q}...

Could anyone give a reference for the following statement, which I believe is true. "Let X be a regular scheme, flat over $Spec( \mathbb{Z}) $, with fiber dimension $1$. Then the Chow group $CH^2(X)$ ...