AGREEMENT Pursuant to Securities Exchange Act Rule 13d-1(k)(1)(iii)

EXHIBIT A

AGREEMENT

Pursuant to Securities Exchange Act

Rule 13d-1(k)(1)(iii)

The undersigned hereby agree that the Schedule 13D, filed pursuant to the Securities Exchange Act of 1934 and executed by each of the undersigned of even date herewith, is filed on behalf of each of the undersigned.

DULY EXECUTED this 23rd day of April, 2001.

/s/ Xxxxxx X. Xxxxxx

Xxxxxx X. Xxxxxx

XXXXXX X. XXXXXX FAMILY

REVOCABLE TRUST, UA DATED 9/8/93

By: /s/ Xxxxxx X. Xxxxxx

Xxxxxx X. Xxxxxx, Trustee

XXXXXX X. XXXXXX REVOCABLE

TRUST DATED 9/8/93

By: /s/ Xxxxxx X. Xxxxxx

Xxxxxx X. Xxxxxx, Trustee

/s/ Xxxx X. Xxxxxx

Xxxx X. Xxxxxx

/s/ Xxxxxxx Xxxxxx Xxxxx

Xxxxxxx Xxxxxx Xxxxx

/s/ Xxxxxxx X. Xxxxx

Xxxxxxx X. Xxxxx

H. XXXXXX XXXXXX AND XXXX X.

XXXXXX 1997 IRREVOCABLE TRUST

By: /s/ Xxxxxxx X. Xxxxx

Xxxxxxx X. Xxxxx, Trustee

/s/ H. Xxxxxx Xxxxxx

H. Xxxxxx Xxxxxx

/s/ Xxxx X. Xxxxxx

Xxxx X. Xxxxxx

/s/ Xxxx Xxxxxx Xxxx

Xxxx Xxxxxx Xxxx

/s/ Xxxx X. Xxxx

Xxxx X. Xxxx

XXXXXXXXX X. XXXXXX TRUST A

By: Arvest Trust Company, N.A., Trustee

By: /s/ Xxxxx Xxxxxxx

Title: Senior Vice President and Trust Officer

XXXXXXXXX X. XXXXXX TRUST B

By: Arvest Trust Company, N.A., Trustee

By: /s/ Xxxxx Xxxxxxx

Title: Senior Vice President and Trust Officer

ARVEST TRUST COMPANY, N.A.

By: /s/ Xxxxx Xxxxxxx

Title: Senior Vice President and Trust Officer

ARVEST BANK GROUP, INC.

By: /s/ Xxxx Xxxxxxx

Title: Vice President