A [class_of_relationship_with_signature] is a [class_of_relationship] that may have a [role_and_domain] specified for each end.
example
EXAMPLE Married is a [class_of_relationship] where class_of_end_1 is the [role_and_domain] husband, and class_of_end_2 the [role_and_domain] wife.
note
NOTE A [class_of_relationship_with_signature] is analogous to a simple EXPRESS attribute and its inverse. More complex objects can be modelled with [multidimensional_object] and [class_of_multidimensional_object].