CONSENT OF ARTHUR ANDERSEN LLP
Published on March 31, 1999
EXHIBIT 23.1
CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
As independent public accountants, we hereby consent to the incorporation by
reference into the Company's previously filed Registration Statements on Form
S-8 (File No. 333-56089), Form S-8 (File No. 333-16837), Form S-3 (File No.
333-16647), Form S-3 (File No. 333-15407), Form S-3 (File No. 333-60875), and
Form S-3 (File No. 333-62855) of our report included in this Form 11-K.
/s/ ARTHUR ANDERSEN LLP
Washington, D.C.
March 29, 1999