Pipes، Louis Albert (1963). Matrix Methods for Engineering. Prentice-Hall International Series in Applied Mathematics. Prentice-Hall. ص. 91. مؤرشف من الأصل في 2020-04-13.
Pipes، Louis Albert (1963). Matrix Methods for Engineering. Prentice-Hall International Series in Applied Mathematics. Prentice-Hall. ص. 91. مؤرشف من الأصل في 2020-04-13.