The citation is ambiguous. It may mean:
37 Stat. 39 (Pub. Res 62-8)
JOINT RESOLUTION To admit the Territories of New Mexico and Arizona as States into the Union upon an equal footing with the original States. August 21, 1911 39
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also:
37 Stat. 38 (Pub. Res 62-7)
JOINT RESOLUTION Providing for additional lands for Colorado under the provisions of the Carey Act. August 21, 1911
Link is to an internal page within a statute beginning on page 38.
You can view this U.S. Statutes at Large citation at these source(s):
PDF - https://govtrackus.s3.amazonaws.com/legislink/pdf/stat/37/STATUTE-37-Pg38a.pdf
also: