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                                                                 EXHIBIT (a)(10)

THE THOMSON CORPORATION
Toronto Dominion Bank Tower, Suite 2706
PO Box 24, Toronto-Dominion Centre
Toronto, Ontario M5K 1A1
Tel (416) 360-8700   Fax (416) 360-8812
www.thomson.com


NEWS RELEASE


INVESTOR CONTACTS:                            MEDIA CONTACTS:
------------------                            --------------
John Kechejian                                Jason Stewart
Vice President, Investor Relations            Director, Public Relations
The Thomson Corporation                       The Thomson Corporation
(203) 328-9470                                (203) 328-8339
john.kechejian@thomson.com                    jason.stewart@thomson.com

Ron Benanto                                   David Scott
Vice President, Chief Financial Officer       Vice President, Marketing
NewsEdge Corp.                                NewsEdge Corp.
(781) 229-3000                                (781) 229-3000
ron.benanto@newsedge.com                      david.scott@newsedge.com

FOR IMMEDIATE RELEASE
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   THE THOMSON CORPORATION EXTENDS CASH TENDER OFFER FOR NEWSEDGE CORPORATION
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TORONTO, SEPTEMBER 18, 2001 - The Thomson Corporation (TSE: TOC) announced today
that InfoBlade Acquisition Corporation (InfoBlade), an indirect wholly owned
subsidiary of Thomson, is extending its offer to acquire all outstanding shares
of common stock of NewsEdge Corporation (NASDAQ:NEWZ) until 12:00 Midnight (EDT)
on September 25, 2001, unless further extended. The cash tender offer and
withdrawal rights were previously scheduled to expire at 12:00 Midnight (EDT) on
September 18, 2001.

      Due to the tragic events that transpired on September 11, 2001 and the
subsequent closing of the stock markets and the interruption of mail service to
the Depositary, Computershare Trust Company of New York, Thomson is extending
the expiration date of the cash tender offer. The decision to extend the offer
was made after consultation with NewsEdge and the Securities and Exchange
Commission. Any questions should be directed to the Information Agent, Innisfree
M&A Incorporated, by calling toll free 1-888-750-5834.

      Thomson currently does not plan any changes in the terms of the cash
tender offer. As of 12:00 PM (EDT) on September 17, 2001, 9,498,647 shares have
been received by the Depositary pursuant to the offer. The cash tender offer is
subject to the tender of at least a majority of NewsEdge shares and other
customary conditions.

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THOMSON EXTENDS TENDER OFFER
September 18, 2001
Page 2

      The cash tender offer is being made in connection with the proposed merger
of InfoBlade and NewsEdge pursuant to an Agreement and Plan of Merger dated as
of August 6, 2001 among Thomson, InfoBlade and NewsEdge. In accordance with the
Merger Agreement, on August 21, 2001, InfoBlade commenced a cash tender offer
for all of the issued and outstanding shares of NewsEdge common stock at a price
of US$2.30 per share. If the proposed merger is consummated, NewsEdge will
become an indirect wholly owned subsidiary of Thomson.

      InfoBlade and Thomson have mailed to registered holders of NewsEdge shares
an Offer to Purchase regarding the cash tender offer, a NewsEdge
Solicitation/Recommendation Statement on Schedule 14D-9, and a Letter of
Transmittal to be used to tender NewsEdge shares in the cash tender offer.
Beneficial owners of NewsEdge holding shares in "street name" through their
brokers may receive the Offer to Purchase and Letter of Transmittal through
Innisfree M&A Incorporated.

      This news release is for informational purposes only. It does not
constitute an offer to purchase shares of NewsEdge or a
Solicitation/Recommendation Statement under the rules and regulations of the
Securities and Exchange Commission. Thomson has filed with the Securities and
Exchange Commission a Tender Offer Statement on Schedule TO and NewsEdge has
filed a Solicitation/Recommendation Statement on Schedule 14D-9. These documents
contain important information and security holders of NewsEdge are advised to
carefully read these documents before making any decision with respect to the
cash tender offer. These documents may be obtained free at the Securities and
Exchange Commission website at www.sec.gov.

ABOUT THE THOMSON CORPORATION

      The Thomson Corporation (www.thomson.com), with 2000 revenues of
approximately US$6 billion, is a leading, global e-information and solutions
company in the business and professional marketplace. The Corporation's
common shares are listed on the Toronto and London stock exchanges.

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