Sentence:  If T(s) = M(s)D(s)^{-1} is a RCMFD[right coprime matrix factor description] of T(s), then M(s) is a <WSD>polynomial basis</WSD> for \mathfrak X_t. If Q(s) is a greatest right divisor of M(s) then T(s) = \overline M(s)Q(s)D(s)^{-1}, where \overline M(s) is a least degree <WSD>polynomial basis</WSD> of \mathfrak X_t [15]. 
Meaning of the word marked with <WSD> tags:  A basis of a polynomial ring (said ring being viewed either as a vector space over the field of coefficients or as a free module over the ring of coefficients).