See Merkurjev
See also Kuku
Something by Karoubi
A decomposition theorem by Vezzosi and Vistoli. See also http://www.math.uiuc.edu/K-theory/0506
arXiv: Experimental full text search
KT (K-theory), AG (Algebraic geometry)?
There are loads of papers of Thomason from the 80s on equivariant K-theory. Return to these if ever needed.
nLab page on Equivariant algebraic K-theory