On the Sequential and Random Selection of Subspaces over a Finite Field. - Eugenio Calabi; Herbert S. Wilf (J. Comb. Theory A, 1977)

Differential and Numerically Invariant Signature Curves Applied to Object Recognition. - Eugenio Calabi; Peter J. Olver; Chehrzad Shakiban; Allen R. Tannenbaum; Steven Haker (Int. J. Comput. Vis., 1998)