We consider the three-dimensional exterior problem for steady Navier-Stokes equations. We prove, under an assumption on the smallness of external data, existence (and uniqueness) of solutions with the same spatial decay at infinity as that of the fundamental solution of the Stokes operator. In this sense the presented result is optimal and naturally completes classical results of Finn .
"Note on decay of solutions of steady Navier-Stokes equations in $3$-D exterior domains." Differential Integral Equations 8 (7) 1833 - 1842, 1995.