Mont. Code Ann. § 35-15-303

At any regularly called general or special meeting of the stockholders of cooperative associations, a written vote received by mail from any absent stockholder and signed by the stockholder may be read in the meeting and must be equivalent to a vote of each of the signing stockholders, provided the stockholder has been previously notified in writing of the exact motion or resolution upon which the vote is taken and a copy of the motion or resolution is forwarded with and attached to the mailed vote.