When Col. Samuel Flagg asks to know Hawkeye's name he states "Dr. Wasserman ... I am looking for a cure for VD and I thought this would be a good place to start." This joke is based on the work of Dr. August von Wassermann who developed a complement fixation test for the early diagnosis of syphilis in 1906.
In this episode we learn that col. Flagg's first name is Sam. Pratt: "buy you a cup of coffee Sam" Col flagg "why not"
Edward Winter previously played a character named Captain Halloran, but this wasn't one of his aliases shown to Lt. Col. Blake.
This is the second of seven times Edward Winter appears on M*A*S*H. He is Col. Samual Flagg. The first time he appeared in S2.E13 , his stage name was Captain Halloran.