Riegel's correspondence in this series is primarily between different awards administrators and judges. Riegel corresponded with approximately 320 different individauls within this subseries. Correspondents of note include Mrs. Dupont, Turner Catledge, and Sol Taishoff.

The two documents in the Radio Conference of Cairo subseries are full text copies of the radio agreements describing acceptable and unlawful use of the radio in attempts to influence populations beyond a nation's borders.

Riegel's Literary Critism course focused on the purpose and manner in which one critiques a written work. Riegel emphasized the different critical theories by different reviewers and had students study reviewers and conduct their own reviews using the fundamentals taught in the course. Items in this subseries consist of course syllabi, class handouts, quizzes, exams, lecture notes, and other material related to the course.

Items in this series pertain to Riegel's personal correspondence between himself and colleagues, friends, and family. Some material is related to or mentions his work, but the majority of the material is about his or other people's personal lives, opinions, and thoughts around world events.