Okla. Admin. Code § 105:1-7-3
The date of filing shall be the date on which any notices are post-marked by the U.S. mail service, proper postage affixed, or the date of personal delivery.
Added at 10 Ok Reg 219, eff 10-28-92 (emergency)
Added at 10 Ok Reg 3551, eff 7-15-93