DDD - How to design associations between different bounded contexts

Question

I have setup a domain project which is being populated with an ORM. The domain contains of different aggregates each with its own root object. My question is how properties that

Answer 1

It depends on what bounded context strategy you use.

If you choose shared kernal, I think it's fine to have a direct relationship between them(direct reference or identifier reference, I believe someone else will explain the pros and cons in other answers). and you've also mentioned these objects integrated by database tables.

But if you choose anti-corruption-layer, you'd better seperate them(use just identifier to keep the relationship), use adapter-translator to integrate(and no database integration).