The Topology of Symmetric, Second-Order 3D Tensor Fields.

Lambertus Hesselink Yuval Levy Yingmei Lavin The Topology of Symmetric, Second-Order 3D Tensor Fields. 1-11 1997 3 IEEE Trans. Vis. Comput. Graph. 1 http://www.computer.org/tvcg/tg1997/v0001abs.htm db/journals/tvcg/tvcg3.html#HesselinkLL97