Portrait of Jordan, from the Johns Hopkins University Press, at approximately 50 years old.

Portrait of Wood at approximately 40 years old.

Portrait of Willoughby at approximately 40 years old.

Portrait of Watson at approximately 33 years old.

Portrait of Watson at approximately 33 years old.

Portrait of Stern at approximately 40 years old.

Portrait of Seligman given to Dr. Karl Menger on the seventieth anniversary of his birthday.

Portrait of Schaeffer at approximately 27 years old.

Portrait of Sabin at approximately 35 years old.

Portrait of Robinson at approximately 30 years old.