Let $X$ be a smooth quasi-projective scheme over a field $k$ and $G$ an algebraic group (also over $k$ not necessarily reductive) acting on $X$.
I the work of Thomason "Equivariant Resolution, Linearization, and Hilbert’s Fourteenth Problem over Arbitrary Base Schemes" it is mentioned that every equivariant coherent sheaf has a finite resolution of equivariant vector bundles. I am searching for a reference for this classical fact.
Thanks in advance!