ABO blood group system letter O for "ohne", meaning without or zero; Landsteiner chose the latter.) This classification was adopted by the National Research Council and became variously known as the National Research Council classification, the International classification, and most popularly the "new" Landsteiner classification. The new system was gradually accepted and by the early 1950s, it was universally followed. The first practical use of blood typing in transfusion was by an American physician Reuben Ottenberg in 1907. And the large-scale application started during the First World War (1914-1915) when citric acid was developed as blood clot prevention. Felix Bernstein demonstrated the correct blood
Blood type (non-human) blood. Two categories of blood groups, human-type and simian-type, have been found in apes and monkeys, and can be tested by methods established for grouping human blood. The rhesus system is named after the rhesus monkey, following experiments by Karl Landsteiner and Alexander S. Wiener, which showed that rabbits, when immunised with rhesus monkey red cells, produce an antibody that also agglutinates the red blood cells of many humans. Data on blood groups of chimpanzees, baboons, and macaques. Two complex chimpanzee blood group systems, V-A-B-D and R-C-E-F systems, proved to be counterparts of the human MNS and Rh-Hr blood group