618 P.2d 1261 CATERPILLAR TRACTOR CO., et al, Appellants, v. DEPARTMENT OF REVENUE, Respondent. NO. 1233, SC 26786Oregon Supreme Court.Argued and submitted September 10, 1980. Affirmed October 21, 1980. Appeal from Judgment of the Oregon Tax Court.[*] [*] Carlisle Roberts, Judge. Margaret M. Baumgardner, Portland, argued the cause for appellants. With her on the briefs […]