1. Linear least squares solution by Householder transformations;Businger;Numer. Math.,1965
2. E.W. Cheney, K.H. Price, Minimal projections, in: Approximation Theory (Proceedings of Symposium, Lancaster 1969), New York, 1970, pp. 261–289.
3. On the conditioning of multipoint and integral boundary value problems;de Hoog;SIAM J. Math. Anal.,1989
4. Matrix Computations;Golub,1983
5. Solving Least Squares Problems;Lawson,1974