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

Many practice bundles repeat a 'minimum speed' question with a specific figure and sometimes an accompanying law article, as if it came straight from this chapter. On the five pages of this chapter that were actually opened (p.117-126), however, that figure appears nowhere. The trap is not the topic itself — it is acting as if every figure you have seen somewhere is also grounded in this book.