Ciarlet, P G; Ciarlet, P; Iosifescu, J O; Sauter, S; Zou, J (2011). Lagrange multipliers in intrinsic elasticity. Mathematical Models and Methods in Applied Sciences, 21(4):651-666.
Ciarlet, P G; Iosifescu, J O; Sauter, S; Zou, J (2010). A Lagrangian approach to intrinsic linearized elasticity. Comptes Rendus Mathematique, 348(9-10):587-592.