system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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publishers, using Document Object Identifier (DOI) and other standards, which may be mutually agreed upon from time to time. 17. Right of Renewal 17.1 The Publishers shall have the right to renew the term of the Services by notice in writing to HealthGate to be given on or before 30 September 1999. If the Publishers exercise their right to renew, the term of the Services shall be extended by one further year, up to and including 28 February 2001. The Use Fees shall remain the same as in the Initial Period and the fee for the Services shall not exceed $7000 for additional journals, $2000 maintenance fee on existing journals and $2000 per Gigabyte. 17.2 If the Publishers exercise their right of renewal under Clause 17.1, then the Publishers shall have a further right of renewal for each of the subsequent three years, provided that the right to renew shall be conditional upon the Publishers having exercised their right in the previous year, and giving notice on or before the 30 September before the renewal is to take effect. 18. Assistance upon Termination On termination of the provision of the Services by HealthGate to the Publishers for any reason: 10 18.1. HealthGate will liaise with the Publishers, making available for such purposes such HealthGate liaison staff as the Publishers may reasonably require, and acting in all good faith, to ensure a mutually satisfactory license to the Publishers or, at the Publishers' option, to a replacement contractor. The period of liaison will commence as soon as notice has been given of termination of this Agreement, and will continue for a maximum period of 3 months after termination; 18.2. HealthGate agrees that at the time of termination of this Agreement, it will render all assistance, provide all documentation and undertake all actions to the extent necessary to effect an orderly assumption of the Services by the Publishers or, at the Publishers' option, by a replacement contractor; 18.3. If the Publishers so require, HealthGate will use its best endeavours to procure the transfer at the Publishers' expense, to the Publishers or to a third party nominated by the Publishers at the Publishers' sole discretion, of any Third Party Software licences HealthGate may have obtained in its own name in order to provide the Services and used for that purpose exclusively; and 18.4. HealthGate will be obliged to satisfy the Publishers that it has erased the Publishers Content and all copies, and that it has no ability to reproduce the Publishers Content in any way. The rights of the Publishers in this Clause 18 are in addition to the rights in Clause 33. 19. Cost and Payment, Change Control Formula 19.1. The total price payable by the Publishers is set out in Clause 19.2 and the Use Fees in Clause 19.4, subject to the terms and conditions in this Agreement, this price being a fixed price. 19.2. Subject to HealthGate performing its obligations hereunder, HealthGate shall invoice the Publishers for payment as follows: 19.2.1. On 30 January 1998 $100,000 19.2.2. On 06 February 1998 $150,000 19.2.3. On acceptance of Specification, $150,000 or 27 February 1998 whichever is later 11 19.2.4. On acceptance of System launch $150,000 19.2.5. On system completion date $150,000 19.2.6. On 1 January 1999 $175,000 19.2.7. On 1 April 1999 $175,000 19.2.8. On 1 July 1999 $175,000 19.2.9. On 1 September 1999 $175,000 PROVIDED ALWAYS THAT if the Agreement is terminated in accordance with Clause 9.4 then the financial provisions of that Clause will apply in place of this Clause 19. 19.3. Invoices are payable within 60 days of receipt, with the exception of payments due under Clause 19.2, which shall be payable on the due date or on acceptance of the work, which ever is the later. 19.4. Use Fees The Publishers shall make payments to HealthGate based upon "Use" of the Content as set forth on the Second Schedule. For the purposes of this Agreement, "Use" shall mean a retrieval or download by a Publishers' subscriber of the full-text of an article. There shall not be any additional use fees or charges for users' browsing of table of contents or abstracts. Use Fees shall be billed by HealthGate monthly and all payments are due by cheque by the end of the following month after the date of the invoice. 19.5. Interest Interest on late payment by either party shall be charged at 2% above base rate for the time being of Barclays Bank plc in England. This sub-Clause 19.5
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Extract the exact clause related to "Renewal Term" from the excerpt above.

assistant: If the Publishers exercise their right to renew, the term of the Services shall be extended by one further year, up to and including 28 February 2001.