Notice issued by Joseph and Hyrum Smith in the Times and Season paper, February 1, 1844 (at the time Joseph had more than 30 plural wives): ¹

“NOTICE
As we have lately been credibly informed, that an Elder of the Church of Jesus Christ, of Latter-day Saints, by the name of Hiram Brown, has been preaching polygamy, and other false and corrupt doctrines, in the county of Lapeer, state of Michigan.

This is to notify him and the Church in general, that he has been cut off from the church, for his iniquity: and he is further notified to appear at the Special Conference, on the 6th of April next, to make answer to these charges.

JOSEPH SMITH
HYRUM SMITH
Presidents of said Church“

…

Footnote 24 – LDS Gospel Topic Essay, Plural Marriage in Kirtland and Nauvoo: ²

“Careful estimates put the number [of Joseph’s wives] between 30 and 40. See Hales, Joseph Smith’s Polygamy, 2:272–73.”