Conceptual and data modeling aspects of this problem are discussed in [1]. It compares links with joins (and foreign keys) by proposing a solution (concept-oriented model) which does not use joins at all but rather relies on links only.

Essentially, a foreign key is viewed as a relational workaround for representing links with some significant drawbacks and the question is why not to use links directly without relational wrapping.

[1] Joins vs. Links or Relational Join Considered Harmful: https://www.researchgate.net/publication/301764816_Joins_vs_...