WAIVER OR MODIFICATION INEFFECTIVE UNLESS IN WRITING
No waiver or modification of this agreement or of any covenant,
condition, or limitation herein contained shall be valid unless in
writing and duly executed by the party to be charged therewith.
Furthermore, no evidence of any waiver or modification shall be offered
or received in evidence in any proceeding, arbitration, or litigation
between the parties arising out of or affecting this agreement, or the
rights or obligations of any party hereunder, unless such waiver or
modification is in writing, duly executed as aforesaid. The provisions
of this paragraph may not be waived except as herein set forth.