Choosing the right official source: Rule 21.4.5(a)(i) & (ii)
NOTE about the Bluebook official sources for U.S. treaties:
U.S.T. and T.I.A.S. are no longer published in print. PDFs of later T.I.A.S. slip treaties are on the Dept. of State website and in HeinOnline.
If your treaty is not in U.S.T. or T.I.A.S., it might be in the other official sources in Bluebook Rule 21.4.5(a)(i) and (ii). Those sources are included in the other two boxes on this page, Pre-1950 official treaty sources and Post-1949 official treaty sources. Those lists also include a few more official government publications that, although not listed in the Bluebook, might contain the text or indicate the status of a treaty before it is ratified, e.g., Senate Executive Reports and presidential communications to the Senate.