52 Pa. Code § 5.421
The provisions of this §5.421 amended under the Public Utility Code, 66 Pa.C.S. § § 309-311, 315, 331-335, 501, 504-506, 523, 701-703, 1101-1103, 1301, 1501 and 1504.
This section cited in 52 Pa. Code § 5.373 (relating to subpoenas); and 52 Pa. Code § 5.424 (relating to issuance of subpoenas).