437 A.2d 1310 William Frederick Holtzapfel, Petitioner v. Commonwealth of Pennsylvania, Workmen’s Compensation Appeal Board and Department of Public Welfare, Respondents. Commonwealth Court of Pennsylvania.Argued May 6, 1981 December 23, 1981. Workmen’s compensation — Occupational disease — Burden of proof — The Pennsylvania Workmen’s Compensation Act, Act of June 2, 1915, P.L. 736 — Incidence […]