After any territory is annexed to or disconnected from any municipality, the chief executive officer of the municipality or of the county board, as the case may be, whenever not otherwise provided in this Code, shall within 90 days file for recordation, in the recorder's office of the county where the territory is situated and also in the county where the annexing and divided municipalities are situated, a certified copy of the ordinance, court order or resolution of annexation or disconnection, together with an accurate map of the territory annexed or disconnected.
65 ILCS 5/7-1-40