United States Steel Corp. v. Commonwealth ( 1978 )
Baltimore O.R.R. v. Penna. P.U.C. ( 1938 )
United Natural Gas Co. v. Pennsylvania Public Utility Commission ( 1943 )
Carpenter v. Pennsylvania Public Utility Commission ( 1940 )
Allegheny Ludlum Steel Corp. v. Pennsylvania Public Utility Commission ( 1949 )