Okla. Stat. tit. 62, § 62-450: Application of act

The provisions of this act are applicable only in cases where

all the bond, interest and judgment indebtedness of such municipal

subdivision for which such sinking fund levies for such previous

years were made and which is or was an obligation of such sinking

fund has either been paid, or is subject to immediate payment out of

unencumbered and unappropriated cash then in said sinking fund, or

refunded or reduced to judgment and legal provision made for payment

thereof out of sinking fund levies, or other wise, within the

current and/or future fiscal years.