the person responsible for the abo classification system for blood is
ABO blood group system The ABO blood group system is widely credited to have been discovered by the Austrian scientist Karl Landsteiner, who identified the O, A, and B blood types in 1900.[5][6] Landsteiner originally described the O blood type as type "C", and in parts of Europe it is rendered as "0" (zero), signifying the lack of A or B antigen. Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930 for his work.[5] Alfred von Decastello and Adriano Sturli discovered the fourth type, AB, in 1902.[7][8]
Blood type (non-human) Over 13 canine blood groups have been described. Eight DEA (dog erythrocyte antigen) types are recognized as international standards.[3][4][5] Of these DEA types, DEA 4 and DEA 6 appear on the red blood cells of ~98% of dogs. Dogs with only DEA 4 or DEA 6 can thus serve as blood donors for the majority of the canine population. Any of these DEA types may stimulate an immune response in a recipient of a blood transfusion, but reactions to DEA 1.1+ are the most severe.