“…One considers bounded candidate constructs and an action on these by the map whose (unique) fixed point (parametrized by a point on the stable subspace) must be an orbit. Perron [Pn1,(13) p. 144], [Pn2,(10) p. 51], [Pn4,(30) p. 719] used a variant of Picard iteration (or variation of parameters) for solutions of differential and difference equations; Irwin [I] simplified this approach and combined it with the Banach Contraction Principle to obtain a short proof with strong conclusions [Ro4, Section 5.10], [We, LW, Yc].…”