Question: Egbert B. Gebstadter is a fictional author who appears in the indexes of books written by an American professor who was born in what year?
Sentence (from "Professor Branestawm"): Written over a 50-year period, between 1933 and 1983, the children's books feature as protagonist the eponymous inventor, Professor Theophilus Branestawm, who is depicted throughout the books as the archetypal absent-minded professor.
Relevant evidence: No