'Karl Landsteiner discovered there were 4 of these: A, B, O & AB'
blood types
THE EARLY 1900s: Karl Landsteiner discovered there were 4 of these: A, B, O & AB
Karl Landsteiner discovered there were 4 of these: A, B, O & AB
Karl Landsteiner discovered there were 4 of these: A, B, O & AB
THE EARLY 1900s
blood types
THE EARLY 1900s