A wine class represents all possible wines
The maker of a wine (a Winery). This slot has an iinverse - the slot produces at the Winery class
This slot contains the wines produced by a particular winery. The maker of a Wine is its inverse slot.
A specific area (such as Napa) where a wine comes from
Schloss Volrad Trochenbierenauslese Riesling
Mount Eden Vineyard Edna Valley Chardonnay
Schloss Rothermel Trochenbierenauslese Riesling
Santa Cruz Mountain Vineyard Cabernet Sauvignon
(forall ?wine (=> (and (own-slot-not-null maker ?wine) (own-slot-not-null area ?wine)) (= (area (maker ?wine)) (area ?wine)) ) )