Hestenes, M. R. (1958). «Inversion of Matrices by Biorthogonalization and Related Results». Journal of the Society for Industrial and Applied Mathematics6 (1): 51–90. doi:10.1137/0106005.
Golub, G. H.; Kahan, W. (1965). «Calculating the singular values and pseudo-inverse of a matrix». Journal of the Society for Industrial and Applied Mathematics: Series B, Numerical Analysis2 (2): 205–224. doi:10.1137/0702016.
Hestenes, M. R. (1958). «Inversion of Matrices by Biorthogonalization and Related Results». Journal of the Society for Industrial and Applied Mathematics6 (1): 51–90. doi:10.1137/0106005.
Golub, G. H.; Kahan, W. (1965). «Calculating the singular values and pseudo-inverse of a matrix». Journal of the Society for Industrial and Applied Mathematics: Series B, Numerical Analysis2 (2): 205–224. doi:10.1137/0702016.