NEG — Page 36, sec 2.5.1: the terminilogy for containment does not align with UML

Page 36, sec 2.5.1: the terminilogy for containment does not align with
UML, which would be a good idea to do and to explicitly say that you are
doing. Weak aggregationi in UML is "shared" aggregation, which doesn't
simply mean that there is no lifecycle dependency. Weak aggregation is not
the same as no aggregation. Weak aggregation means that an aggregee
instance can be aggregated by more than one aggregate at the same time, and
that the aggregee doesn't go away until the last owning aggregate goes
away. That's why it's called "shared" aggregation. Containment is not a
formally specified notion in UML, and composition is strong aggregation.
So the three possibilities for aggregation semantics are:
1) no aggregation
2) shared (weak) aggregation
3) composite (strong) aggregation