Lozovaya, Russia 1910: Author's parents Chicago 1924: Author Lozovaya, Russia 1914: Author Fairbanks, Alaska 1942: Author
Lozovaya, Russia 1910: Author's parents
Chicago 1924: Author
Lozovaya, Russia 1914: Author
Fairbanks, Alaska 1942: Author
Chicago 1949: Author and Gwen Goodrich shortly after their marriage
Toronto 1986: Author On blackboard matrix representation of Prisoner's Dilemma