Any notices required or permitted to be given under this Agreement shall be delivered by hand, mailed by certified or registered mail, return receipt requested, in a postage prepaid envelope, or delivered by a nationally recognized overnight delivery service, and addressed as described below; notices shall be deemed effective only upon receipt or refusal of delivery. Notices may also be given by facsimile effective as of the date of receipt (or, if not a business day, the first business day thereafter).