  This paper is mainly concerned with the robustly stable adaptive control of
single-input single-output impulse-free linear time-invariant singular dynamic
systems of known order and unknown parameterizations subject to single external
point delays. The control law is of pole-placement type and based on
input/output measurements and parametrical estimation only. The parametrical
estimation incorporates adaptation dead zones to prevent against potential
instability caused by disturbances and unmodeled dynamics. The Weierstrass
canonical form is investigated in detail to discuss controllability and
observability via testable conditions of the given arbitrary state-space
realization of the same order.
