Ward-Takahashi identities from symmetry

nlieb
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Does anyone know how to derive the Ward-Takahashi identity for a field starting from a known conserved Noether current (or equally helpful, from a known symmetry transformation of the Lagrangian)? It'll probably be enough to allow me to do it for myself if you could explain quantitatively what the Ward-Takahashi identity is. Please don't quote wikipedia to me, from a pedagogical standpoint it has all the teaching prowess of an amoeba.
 
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Srednicki's http://web.physics.ucsb.edu/~mark/ms-qft-DRAFT.pdf" , equation 67.8 onwards has some relevant discussion.
 
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