The design of Kreiger's sub is an exact copy of the Confederate submarine H. L. Hunley, sunk in 1864 during the American Civil War.
When Krieger confesses to sinking his sub, he falls to his knees, pounds the floor, and shouts, "I blew it up. God damn you all to hell, I blew it up". This is imitating Charlton Heston at the end of Planet of the Apes (1968).
Sterling at one point calls Mallory a "cold-blooded prehistoric monster". Jessica Walter, who plays Mallory, played Fran Sinclair in Dinosaurs (1991), a show about actual cold-blooded, prehistoric monsters.