1 EXHIBIT 23.1 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation of our reports included in this Form 10-K, into the Company's previously filed Registration Statements (SEC File No. 333-08249, 333-08251, 333-08257, 333-08303 and 333-36785). Arthur Andersen LLP San Antonio, Texas December 24, 1997