In Green v. Jones (1964) 23 Wis. 2d 551 128 N.W.2d 1, the trucking company contracted with the material suppliers to deliver the materials for some projects and contracted directly with the general contractor for delivery to other projects. Green held that the trucking company drivers were covered by the prevailing wage law because the materials they delivered were immediately distributed over the roadway surface. Their tasks "were functionally related to the process of construction." (Green, supra, 128 N.W.2d at p. 7.) As soon as the driver dumped or spread the material, it was leveled by graders or mixed with cement under the general contractor's supervision. "The delivery of materials was an integrated aspect of the 'flow' process of construction." (Ibid.)