Perhaps there are lots of subtle references to things Amicable in the outside world.

And there are a couple of very subtle references to Beethoven.

Some of the episodes carry subtle references to the world war 2 also.

The show often features subtle references to classic science fiction.

The lines also included a subtle reference to the belief 50 Cent had at one point been a police informant.

This episode contains several other subtle references to the same film.

The phrase is a subtle reference to the notion of one's brain becoming waste.

I placed subtle references throughout the costumes in the show.

They banned all subtle and not-so-subtle references to social or financial success.

One of the campaign's simple pleasures is making subtle references to soft drink advertising.