36 Pa. Stat. § 659.4
All revenue bonds, notes or other obligations hereafter issued by the commission shall bear the facsimile signatures of the Governor and the chairman of the commission, and the facsimile of the official seal of the commission shall be affixed thereto and attested by the secretary and treasurer of the commission, and any coupons attached thereto shall bear the facsimile signature of the chairman of the commission. In case any officer whose signature or a facsimile thereof shall appear on any bonds, notes or other obligations or coupons shall cease to be such officer before the delivery of such bonds, notes or other obligations, such signature or the facsimile thereof shall nevertheless be valid and sufficient for all purposes, the same as if he had remained in office until such delivery.
36 P.S. § 659.4