About a property of a class of linear time-varying systems derived from the controllability and observability matrices

This correspondence deals with an application of a theorem of Silverman and Meadows which specifies conditions for
n
time-variable
n
-dimensional vectors to be linearly dependent. From this theorem conditions are derived which allow one to verify whether a linear time-varying system admits a realization in which either the state matrix
A
and the state-input matrix
B
, or the state matrix
A
and the state-output matrix
C
, are constant.