1. Biproportional Matrices and Input-Output Change;Bacharach,1970
2. An algorithm for quadratic optimization over transportation polytopes;Bachem;Z. Angew. Math. Mech.,1978
3. Estimating input-output matrices;Bachem,1977
4. Manifestations of the Schur complement;Cottle;Linear Algebra and Appl.,1974
5. R.W. Cottle, private communication.