[storm] beginner's question...

[Massimo]

Hi everybody,
I'm new to storm, I find it's very interesting, and I'm playing with the 
tutorial to improve my knowledge.

I would need a better understanding of the ReferenceSet with composed 
primary key.
I still have no real case, but I'm figuring a scenario like the following:

Class A, with a composed primary key of n fields (n>2).
Class B, n:1 related with A, so it should have n fields for the foreign 
composed key (and hopefully other fields, i suppose...).

How should the ReferenceSet appear in class B?
 From tutorial I can understand only 2 fields for the composed primary 
key (ref: "Many-to-many reference sets and composed keys) and I can't 
understand how to use it with n>2 pk fields.

Thanks in advance for the help,
Massimo.