McDonnell Douglas Corp. v. Green , 93 S. Ct. 1817 ( 1973 )
Texas Department of Community Affairs v. Burdine , 101 S. Ct. 1089 ( 1981 )
United States v. Singer Manufacturing Co. , 83 S. Ct. 1773 ( 1963 )
United States v. Powell , 105 S. Ct. 471 ( 1984 )