Rank of 3-tensors with 2 slices and Kronecker canonical forms
  Tensor type data are becoming important recently in various application fields. We determine a rank of a tensor T so that A+T is diagonalizable for a given 3-tensor A with 2 slices over the complex and real number field. 
Toshio Sumi, Mitsuhiro Miyazaki and Toshio Sakata