What is the test for a non-discriminatory use or beneficial possession tax on federally owned property?

5 The court's reference to a "nondiscriminatory tax" is an acknowledgment of the principle that one limitation on imposing a use or beneficial possession tax on federally owned property is that such a tax cannot discriminate against either the federal government or those who deal with the federal government. (See, e.g., United States v. City of Detroit, supra, 355 U.S. at p. 473, 78 S.Ct. at p. 478, and City of Detroit v. Murray Corp., supra, 355 U.S. at p. 494, 78 S.Ct. at p. 461.)