UNIFORM VALIDITY OF DISCRETE FRIEDRICHS' INEQUALITY FOR GENERAL NONCONFORMING FINITE ELEMENT SPACES
Petr Knobloch · Numerical Functional Analysis and Optimization · 2001
We prove the uniform validity of discrete Friedrichs' inequality for general nonconforming finite element spaces defined over triangulations consisting of triangles and/or quadrilaterals. The result is valid for arbitrary polygonal domains and also for locally refined triangulations.