This Agreement may be amended, modified, or superseded, and any of the terms hereof may be waived, only by written instrument executed by the parties hereto or in the case of a waiver, by the party waiving compliance.  The failure of any party at any time to require performance of any provision hereof shall in no manner affect the right at a later time to enforce the same.  No waiver by any party of any term continued in this Agreement shall be deemed or construed as a further or continuing waiver of any such breach in any subsequent instance or a waiver of any such breach in any subsequent instance or a waiver of any breach of any other terms contained in this Agreement.