Before revision: In the context of flow visualization a triple decomposition of the velocity gradient  was proposed by Kolat in 2007 who demonstrated the technique in two dimensions, which was later realized in three dimensions by Nagata et al. in 2020.
After revision: In the context of flow visualization a triple decomposition of the velocity gradient into irrotational straining flow, shear flow and rigid body rotational flow was proposed by Kolat in 2007 who demonstrated the technique in two dimensions, which was later realized in three dimensions by Nagata et al. in 2020.