@inproceedings{paperid:1016454, author = {Soheili, Ali Reza and S. SALAHSHOUR and M. MAHDAVIE}, title = {Optimal approximation problem}, booktitle = {4th seminar in linear algebra and its applications}, year = {2007}, location = {رفسنجان, IRAN}, keywords = {Reflexive Matrix;Inverse eigenvalue problem;Optimal Approximation;Moore-Penrose generalized inverse of A.}, }