The failure of a party hereto at any time or times to require performance of any provision hereof shall in no manner affect its right at a later time to enforce the same. No waiver by a party of any condition or of any breach of any term, covenant or representation contained in this Agreement shall be effective unless in writing, and no waiver in any one or more instances shall be deemed to be a further or continuing waiver of any such condition or breach in other instances or a waiver of any other condition or breach of any other term, covenant or representation.</p> <p>19.4.