1. Barrodale , I. Roberts , F. D. K. 1972 l 1 Mathematics Dept. Report 69 University of Victoria Victoria, British Columbia
2. An improved algorithm for discrete l1 linear approximation;Barrodale;SIAM Journal on Numerical Analysis,1973
3. Algorithms for best L1 and L∞ linear approximation on a discrete set;Barrodale;Numerische Mathematik,1966