1. The analysis of asymmetry and orthogonality;Gower,1977
2. The approximation of one matrix by another of lower rank;Eckart;Psychometrika,1936
3. Theory of multidimensional scaling;De Leeuw,1982
4. Some remarks on orthogonality in the analysis of asymmetry;Gower,1992
5. The Theory of Matrices (two volumes);Gantmacher,1959