The 1910 United States Census for Oklahoma has a Special Inquiry for those with Degree of Indian Blood.  Although The Dawes Commission did not enroll many persons of African Descent on the By Blood rolls, the 1910 clearly shows their was Indian Blood. How they figured the degree of Blood eludes any sense of comprehension, but degrees were listed for a few African-Natives.  This is not a comprehensive list.   These handwritten records were difficult to read, therefore the spelling in some cases may be in error.  If the counties listed below have a hyperlink, there were African-Natives found with Degree of Indian Blood.  I have included the sheet number to assist you in obtaining copies.