Let G be a finite group, p prime, and (K,O,F) p-modular system. We prove that the trivial source ring of OG is isomorphic to coherent G-stable tuples (χP), where χP virtual character K[NG(P)/P], P runs through all p-subgroups G, coherence condition equality certain values. use this result describe group orthogonal units as product unit Burnside fusion system with (φP) homomorphisms NG(P)/P→F×. ...