Whenever, by this division or any ordinance of the city, any parking time limit is imposed or parking is prohibited on designated streets, it shall be the duty of the city traffic engineer to erect appropriate signs giving notice thereof and no such regulations shall be effective unless such signs are erected and in place at the time of any alleged offense.

(Code 1964, § 12.586)

     State law reference(s)--Similar provisions, RSMo. § 300.545.