This question already has an answer here:
Say I want to mention an author and their work, i.e. The Beatles—Abbey Road or Herman Melville—Moby Dick, which dash should go betwixt the two?
This question has been marked as a possible duplicate of Appropriate dash to use when attributing a quotation? However, my question is very different as I want to attribute a work, not a quote. The dashes are used quite differently in the opposing scenarios.
What can be inferred from the other question is that em dashes are used for quote attribution.