When the leader of the assault team says, "Stay frosty, boys," it is an homage to "Aliens," when Hicks says the same thing when entering the facility with his assault team. (Coincidentally, his team was massacred, as well.) Also, the scene in which the research facility is monitoring their soldiers via radar tracking devices in the tunnels of the Upside-Down is reminiscent of (and quite possibly an homage to) "Aliens," which also featured actor Paul Reiser.