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I found a family tree with Leonard and Ola Mae Greenlee in it. It is on Ancestry.com. ancestry is a pay website but they give a free trial..owner of the tree is Pamela Willis you can contact her by clicking on her name at top of page....... here is the link to the family tree https://www.ancestry.com/family-tree/person/tree/9905362/person/162013631466/story
She has their marriage date as Nov. 23, 1930, took place in Castle, Oklahoma.
Dear Ms. Gagnon,
Thank you for posting your request on History Hub!
Oklahoma marriage bonds, affidavits, licenses, and certificates were kept by each county beginning about 1890 or when the county was created. Therefore we suggest that you contact the Okfuskee County Clerk for the marriage certificate of Louie Leonard Greenlee and Ola Mae Sexton. Also, please review the FamilySearch Research wiki for Oklahoma Marriage Records.
We hope this is helpful. Best of luck with your family research!