A family of symmetric mixed finite elements for linear elasticity on   tetrahedral grids
  A family of stable mixed finite elements for the linear elasticity on tetrahedral grids are constructed, where the stress is approximated by symmetric $H(\d)$-$P_k$ polynomial tensors and the displacement is approximated by $C^{-1}$-$P_{k-1}$ polynomial vectors, for all $k\ge 4$. Numerical tests are provided. 
Jun Hu and Shangyou Zhang
math.NA