“…These approximations will, in general, be different from the "exact" collocation approximation u defined by (1.1.6); due to the differing quadrature errors associated with (1.2.2a) and (1.2.2b) we have also # . However, the approximations u, t, and t all exhibit the same order of (global and local) convergence; in particular, we have the following results (see, e.g., Brunner and van der Houwen [10]; compare also de Hoog and Weiss [15], Brunner [7] only for (t,s)S but also for (t,s)S':={(t,s)'O<-_s<-_t+8}IxI, for some 3>0. This is, of course, a consequence of the special form of the quadrature approximation (1.2.2a).…”