1. Barrlund, A.: Constrained least squares methods for non-linear differential algebraic systems. Technical report, University of Umeåa Sweden, Institute of Information Processing (1991)
2. Campbell, S.L.: A general method for nonlinear descriptor systems: an example from robotic path control. Technical Report CRSC 090588-01, North Carolina State University Raleigh (1988)
3. Campbell, S.L., Griepentrog, E.: Solvability of general differential algebraic equations. SIAM J. Sci. Comput. 16(2), 257–270 (1995)
4. Campbell, S.L., Kunkel, P.: Applications of Differential-Algebraic Equations: Examples and Benchmarks, Chapter General Nonlinear Differential Algebraic Equations and Tracking Problems: A Robotics Example. Differential-Algebraic Equations Forum. Springer, Cham (2019)
5. De Luca, A.: Control properties of robot arms with joint elasticity. Analysis and control of nonlinear systems. In: 8th International Symposium on Mathematical Networks System. Selected Paper Phoenix, 1987, pp. 61–70 (1988)