1. Applications of the Theory of Quadratic Forms in Hilbert Space to the Calculus of Variations;Hestenes;Pacific J. Math.,1951
2. Power Gain in Feedback Amplifier;Mason;IRE Trans. on Circuit Theory,1954
3. Remarks on the Basis of Network Theory;Redheffer;J. Math. Phys.,1950
4. Inequalities for a Matrix Riccati Equation;Redheffer;J. Math. Mech,1959
5. Supplementary Note on a Matrix Riccati Equation;Redheffer;J. Math. Mech.,1960