On the parallel solution of tridiagonal systems by wrap-around partitioning and incomplete LU factorization. Markus Hegland — 1991 Numerische Mathematik
Multidimensional smoothing using hyperbolic interpolatory wavelets. Hegland, Markus; Nielsen, Ole M.; Shen, Zuowei — 2004 ETNA. Electronic Transactions on Numerical Analysis [electronic only]