Before entering the Cryo-Chamber Vessel, Lance Hunter and Leo Fitz quotes the last dialogue between Leila Organa and Han Solo before Solo is freezed into a carbonite block
When Fitz and Hunter break into the military warehouse to retrieve the cryochamber, the crate containing the Ark of the Covenant can be seen on an upper shelf, identifiable by the Nazi eagle stenciled on the side, with the swastika burned out.
When entering the military base, Hunter and Fitz give the false names of Peltzer and Futterman. These are surnames of characters from the movie Gremlins.