Ruaumoko:
Linear Elastic Hybrid-Stress (Type II) Plane Stress finite element with three degrees of freedom at each node (local x and y displacements and rotation about z axis). There is a cubic lateral displacement on each edge (this matches an adjoining beam or frame member displacement) and a linear longitudinal displacement on each edge.

Ruaumoko3D:
1. Linear Elastic Hybrid-Stress (Type II) Plane Stress finite element with three degrees of freedom at each node (local x and y displacements and rotation about z axis). There is a cubic lateral displacement on each edge (this matches an adjoining beam or frame member displacement) and a linear longitudinal displacement on each edge.

2. Linear Elastic Hybrid-Stress Plate Bending finite element with three degrees of freedom at each node, an out-of-plane displacement and rotations about the two in-plane local axes. A plate shear deformation term may be added in this element.

3. A combination of the above two elements to form a shell finite element with six degrees of freedom at each of the four nodes.