KERML11 — OCL for importedMemberships is incorrect

In 8.3.2.4.5 Namespace, the description of the operation importedMemberships is:

Derive the importedMemberships of this Namespace as the importedMembership of all ownedImports, excluding those Imports whose importOwningNamespace is in the excluded set, and excluding Memberships that have distinguisibility collisions with each other or with any ownedMembership.

However, the OCL does not seem to cover the part about the exclusion of "Memberships that have distinguisibility collisions with each other or with any ownedMembership".