All notices required hereunder shall be given by telephone (confirmed in writing) or shall be in writing and personally delivered or sent by facsimile transmission, reputable overnight delivery service or certified United States mail, postage prepaid, and addressed to the respective parties at their addresses set forth on Exhibit A or otherwise as inform ed to the other part ies by written notice given as aforesaid.  All written notices so given shall be deemed effective upon receipt or, if mailed, upon the earlier to occur of receipt or the expiration of the fourth day following the date of mailing.