an Entity references as follows:
Scope note: This symmetric property associates two instances of E92 Spacetime Volume that have no extent in common Examples: - the "Hallstatt" period (E4) is separated from the "La Tène" era (E4) In First Order Logic: P133(x,y) ⊃ E92(x) P133(x,y) ⊃ E92(y) P133(x,y) ⊃ P133(y,x)