S. Burbulla, and C. Rohde. Finite Volumes for Complex Applications IX - Methods, Theoretical Aspects, Examples, page 547-555. Cham, Springer International Publishing, (2020)
C. Bahlmann, B. Haasdonk, and H. Burkhardt. Proc. of the 8th International Workshop on Frontiers in Handwriting Recognition, page 49--54. IEEE Computer Society, (2002)