On the bramble-hilbert lemma
Lyubomir T. Dechevski, Ewald G. Quak · Numerical Functional Analysis and Optimization · 1990
The aim of this paper is to give an improvement of a result by Bramble and Hilbert [2] concerning upper bounds for linear functionals on certain Sobolev spaces by showing that the constants in the estimate are independent of the bounded Lipschitz domain Ω.