Core: Minimum speed: why this topic (currently) has no book citation here

This atom exists to cover a real CBR topic — minimum speed, often tied to the G3 sign ('mandatory minimum speed') or to the rule that certain slow vehicles may not use the motorway — but this chapter's survey could not find any citation on p.117-126 covering that specific content. For two reasons, nothing with a number or a specific law article is taught here: 1. Zero-invention rule: inventing a figure or article number because it 'probably matches' is exactly the kind of error this whole chapter is trying to fix (see the braking-distance error elsewhere in this chapter, F2). 2. Wrong page, not wrong topic: the topic itself does exist in Dutch traffic law — it likely just belongs to a different chapter (for example the traffic-signs chapter) that has not yet been opened for this atom. What IS established is the adjacent, general topic on p.121-122: do not drive unreasonably slowly, because it obstructs other traffic. That is a courtesy/safety duty, not a specific minimum-speed figure, and is mentioned here only for orientation — it is not tested.