Premise: William Harrison Clanton ( 1862 -- October 26 , 1881 ) was an outlaw Cowboy in Cochise County , Arizona Territory . William Neal Harrison ( October 29 , 1933 -- October 22 , 2013 ) was an American novelist , short story writer , and screenwriter .
Hypothesis: Billy Clanton's full name is William Harrison Clanton.
Label: ENTAILMENT