Anderson, Brian D.O.Bitmead, Robert R.2026-01-022026-01-020018-9286ORCID:/0000-0002-1493-4774/work/174739810https://hdl.handle.net/1885/733802976Column or row properness of matrix fraction descriptions (MFD) may be interpreted as coprimeness at infinity. A bilinear mapping of the complex plane is used to discern a structure at Wity and tbe results are established by considering the dynamic behavior of the system described by the MFD. A criterion for the equivalence of MFD's at dl points including infinity is presented also.2en197810.1109/TAC.1978.11019160018058471