Okla. Stat. tit. 22, § 22-747: Forgery of bill or note of corporation or bank, proof on

trial for.

Upon a trial for forgery any bill or note purporting to be a

bill or note of an incorporated company or bank, or for passing or

attempting to pass, or having in possession with intent to pass, any

such forged bill or note, it is not necessary to prove the

incorporation of such bank or company by the charter or act of

incorporation, but it may be proved by general reputation, and

persons of skill are competent witnesses to prove that such bill or

note is forged or counterfeited.