Title:       Discrete Sobolev and Poincare inequalities via Fourier series 
 
Authors:     Susanne C. Brenner and Li-yeng Sung

Published:   East-West Journal of Numerical Mathematics
             v. 8 (2000), 83--92 (MR# 2001g:42003)

Abstract:    Discrete Sobolev and Poincare inequalities for finite element 
             functions are derived and proved to be sharp via Fourier series.