Ratification of previous adoptions by reference. Any county which has heretofore enacted a code or public record by reference thereto shall not be required to re-enact such code or public record by reason of this Division, and all previous incorporations by reference which would have been valid if this Division had then been in effect, are hereby ratified and declared effective, provided, however, that the requisite number of copies are forthwith filed with the county clerk, if they have not already been so filed.