The ribbons on the service coat Felix wore in Oscar's apartment are in the correct order of precedence. However, the ribbon rack he wears on his shirt in the barracks is upside down.
During the wedding ceremony, the justice of the peace reveals that Oscar Madison's middle name is Trevor, and that his new bride's full name is Blanche Somers (played by Brett Somers, Jack Klugman's real-life wife at the time).
As Blanche joins Oscar in the Army barracks where he is confined on their wedding night, the theme from Romeo and Juliet (1968), by Nino Rota, is heard on the soundtrack.
Oscar is wearing his name tape on wrong side; it should be worn on the right side of the chest.
The part of Crystal was played by executive producer Garry Marshall's ten year old daughter Lori Gay Marshall; neice of both Penny Marshall (merna turner) and The Odd Couples associate producer Tony Marshall.