In the kitchen scene, BJ makes a play on words. He says "Look out, Dagwood" This is a reference to both a "Movie Tone News" segment featured just prior to the scene about a ping pong playing cat and a "Dagwood" sandwich. The sandwich was named for Dagwood Bumstead, a comic strip character known for making huge sandwiches.
Klinger tells the sergeant that the hospital is " a beautiful white building with a statue of Lionel Barrymore in front ". This is a nod to the Dr Kildare movies. Barrymore played Dr. Gillespie.
The poem BJ quotes from is Caroline Elizabeth Sarah Norton's Bingen on the Rhine.
Comedian Joe E. Brown, shown in the newsreels, was born in Holgate Ohio but grew up in Toledo, Klinger's home town.
Some of the newsreel footage is from the spring of 1951, which is about 18 months before Col. Potter arrived at the 4077th, per Change of Command (1975). Rita Hayworth returned to the U.S. with her daughters in March 1951. That is when she gave her "hot dog" speech seen in the episode. And the ticker tape parade for Gen. MacArthur shown in the episode was on April 20, 1951.