In the 1930s when it was more involved in determining classification of American Indians, the federal government used five factors to certify individuals who claimed to be more than half-blood Indian: tribal rolls, testimony of the applicant, affidavits from people familiar with the applicant, findings of an anthropologist, and testimony of the applicant that he has retained "a considerable measure of Indian culture and habits of living." The attempt to use physical characteristics to define Indians created some paradoxical situations. In 1939, for example, the BIA sent Harvard anthropologist Carl Selzer to Robeson County, North Carolina to review the claims of the Lumbee, who were of mixed-race descent. Using methods of assessment then used in physical anthropology, but since discounted, "He measured their features and put a pencil in each Indian's hair, noting 'Indian' blood if the pencil slipped through and 'Negroid' if it did not. The absurd results of his study listed children as Indian while omitting their parents, and placing brothers and sisters on opposite sides of the half-blood line."