Whenever a loan of money is made, it is presumed to be made upon interest, unless it is otherwise expressly stipulated at the time in writing.
Okla. Stat. tit. 15, § 263
Loan presumes interest
R.L.1910, § 1001.
Official source: Oklahoma Legislature. Reproduced from public-domain Oklahoma statutes; confirm against the official source for the current text. Not legal advice.