1. Bilinear systems: An appealing class of "nearly linear" systems in theory and applications
2. Bilinear Control Processes, Academic Press, New York and London, 1973.
3. and , ‘Controllability and optimal control of bilinear systems’, University of New Mexico, Techn. Rep. EE 143, June 1967.
4. and , ‘Lie algebras and linear differential equations’, in Ordinary Differential Equations, Academic Press, London, 1972.
5. and , Geometric Methods in System Theory, Reidel Publishing Co., Dordrecht-Holland, 1973.