This is the same whompage level as 18/51 strength, 2 ranks over straight-18 (which is likely +2/+2 in 3E).

The invention of a derivative of a finite partially ordered set by Nazarova and Roiter in the late 1960s or early 1970s was a seminal event in the subject of representations of finite partially ordered sets (see [Simson 92]).

Attached to a house in the churchtown is a tablet inscribed thus:— […]

Rigging and rifling all ways, and no noise / Made with thy soft feet, where it all destroys.