Okla. Stat. tit. 21, § 21-498: Degree of proof required

(a) Proof of guilt beyond a reasonable doubt is sufficient for

conviction under this act, and it shall not be necessary also that

proof be by a particular number of witnesses or by documentary or

other type of evidence.

(b) Lack of materiality of the statement is not a defense but

the degree to which a perjured statement might have affected some

phase or detail of the trial, hearing, investigation, deposition,

certification or declaration shall be considered, together with the

other evidence or circumstances, in imposing sentence.

(c) In a prosecution for perjury by contradictory statements, as

defined in Section 496 of Title 21, it is unnecessary to prove

which, if any, of the statements is not true.