Whenever any notice is required or permitted hereunder, such notice must be in writing and personally delivered or sent by mail. Any such notice required or permitted to be delivered hereunder shall be deemed to be delivered on the date on which it is personally delivered, or, whether actually received or not, on the third Business Day after it is deposited in the United States mail, certified or registered, postage prepaid, addressed to the person who is to receive it at the address which such person has theretofore specified by written notice delivered in accordance herewith. Company or Employee may change, at any time and from time to time, by written notice to the other, the address which it or he had previously specified for receiving notices.