1) E. Emre, et al.: New Criteria and System Theoretic Interpretations for Relatively Prime Polynomial Matrices, IEEE Trans. on Automatic Control, AC-22, 239/242 (1976)
2) L. M. Silverman and H. J. Poyne: Input-Output Structure of Linear Systems with Application to the Decoupling Problem, SIAM J. Control, 9-2, 199/233 (1971)
3) E. G. Gilbert: The Decoupling of Multivariable System by State Feedback, SIAM J. Control, 7-1, 50/60 (1969)