Mr. Treves in the novel does not have a first name. In the program Towards Zero he's given the first name Frederick.
In an early scene, a character asks for Room 412. This references a famous joke from one of Stan Freberg's routines "St George and the Dragonet" which was a #1 hit record in 1953 and was a popular in-joke at one time in acting circles. The joke's punchline - the Dragnet-style cop says "I've got you on a 412 as well." What's that, shouts the criminal. "Over-acting" replies the deadpan cop.
In the opening, the hotel manager is on the telephone where he can be heard saying "Miss Otis regrets she's unable to lunch today". This is a line from the 1934 Cole Porter song Miss Otis Regrets.
Bertram's Hotel is named after Brown's hotel.