Krawchuk v. Philadelphia Electric Co. , 497 Pa. 115 ( 1981 )
Liuzzo v. McKay , 396 Pa. 183 ( 1959 )
Russell v. Workmen's Compensation Appeal Board , 121 Pa. Commw. 436 ( 1988 )
Michaelson v. Workmen's Compensation Appeal Board , 126 Pa. Commw. 542 ( 1989 )