EXHIBIT 23.01 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation of our report included in this Annual Report on Form 10-K, into the Company's previously filed Registration Statement File No.'s 333-10315, 333-32951, 333- 48451, 333-83715, 333-42202 and 333-81656. ARTHUR ANDERSEN LLP Omaha, Nebraska, March 26, 2002