Would that have been the Dutch Resistance, or some other group?

(I know that part of the problem with Operation Market Garden was that by the time that one rolled around, it had become clear that most of the agents in the Dutch Resistance had been killed or compromised, and nobody was trusting any intel that came out of the Netherlands anymore -- so that when actual good intel came in about a Panzer division operating in the area, nobody in British intelligence believed it.)