Are there any federal decisions that determine whether a search warrant is valid at a border search?

Appellant also argues that the federal decisions involve border searches and are not authoritative; she states that border searches are governed by special rules only applicable thereto. As the court said in People v. Jones, supra, 20 Cal.App.3d 201, 208, 97 Cal.Rptr. 492, 496, the only reason that '. . . border searches are different from other kinds of searches is that probable cause is not required, . . .' In this case, there was no question of probable cause.