for a1, a2, v, v1, v2 being object
for V, A being set st {v,v1,v2} c= V & v <> v1 & a2 in A & not v1 .--> a1 in A & not v .--> (v2 .--> a2) in A & a1 is TypeSCNominativeData of V,A holds
local_overlapping (V,A,(v1 .--> a1),(v2 .--> a2),v) = (v,v1) --> ((v2 .--> a2),a1)