146 N.W.2d 306 ROBERT M. BORDEN et al., appellants, v. MARVIN R. SELDEN, JR., State Comptroller, et al., appellees. No. 52367.Supreme Court of Iowa. November 15, 1966. STATUTES: Presumption of constitutionality. All presumptions 1 are in favor of the constitutionality of a statute and it will not be held invalid unless it is clear, plain […]