Each averaging technique yields reliable a posteriori error control in FEM on unstructured grids. Part II: Higher order FEM.

Sören Bartels Carsten Carstensen Each averaging technique yields reliable a posteriori error control in FEM on unstructured grids. Part II: Higher order FEM. 971-994 2002 71 Math. Comput. 239 db/journals/moc/moc71.html#BartelsC02