Okla. Stat. tit. 22, § 22-746: Bigamy, proof on trial for

Upon a trial for bigamy, it is not necessary to prove either of

the marriages by the register, certificate or other record evidence

thereof, but the same may be proved by such evidence as is

admissible to prove a marriage in other cases, and when the second

marriage took place out of the state, proof of that fact accompanied

with proof of cohabitation thereafter in this state, is sufficient

to sustain the charge.