The examples in Bluebook, 20th ed., Rule 21.11(d) (which incorporates by reference Rule 21.4.5) and the suggested official citations below do not include any U.S. treaty sources because the U.S. did not ratify the Uruguay Round agreements as treaties, but instead implemented them through legislation and administrative action.
For citation to the Bluebook-preferred official U.N.T.S. and unofficial I.L.M., as well as additional sources, see Citing the WTO Agreements.