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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the PaperExchange Site from any Pulp and Paper Online Competitor. 5. CO-MARKETING ACTIVITIES 5.1. Trade Shows and Conventions. 5.1.1. During the Term, PaperExchange shall use commercially reasonable efforts to expand its presence at major national and international pulp and paper industry trade shows and conventions, including booth exhibitions, attendance by industry veteran sales force from all the major paper grades and industry panel sponsorships, when available. PaperExchange, in its reasonable business discretion, shall actively engage in co-branded activities with VerticalNet at PaperExchange's booth exhibitions and shall maintain an open invitation policy for VerticalNet to send its own sales force to co-locate, subject to Section 5.1.3 [Trade Shows and Conventions], with PaperExchange at its trade show booths. 5.1.2. VerticalNet, in its reasonable business discretion, shall offer PaperExchange 7 exhibit booth space at pulp and paper industry trade shows that VerticalNet is unable to use on the same terms that VerticalNet accepted for such space. 5.1.3. When VerticalNet and PaperExchange are both attending pulp and paper industry trade shows, VerticalNet and PaperExchange shall work together to share costs of such trade shows and related material. 5.2. Sales Force Visits. PaperExchange shall use commercially reasonable efforts to (a) expand its sales force presence on a national and international basis, in all major paper grades and (b) commit its sales force to promote Pulp and Paper Online through "on-the-ground" activities including site visits to mills, converters, printers and brokers. 5.3. Advertising Campaigns. 5.3.1. PaperExchange shall, in its reasonable business discretion, promote the PaperExchange Site through print medium. 5.3.2. VerticalNet shall, in its reasonable business discretion, promote Pulp and Paper Online through print medium. 5.3.3. VerticalNet and PaperExchange shall co-promote the PaperExchange Home Page and Pulp and Paper Online in mutually agreeable advertising and collateral marketing material. All co-promotion advertising materials produced by or on behalf of either party (the "Originating Party") shall be subject to the written approval of the other party (the "Receiving Party"), which approval shall not to be unreasonably withheld, delayed or conditioned. The Receiving Party shall notify the Originating Party of its approval or disapproval of such advertising materials as soon as practicable, but in any event within five business days after Receiving Party's receipt thereof. Any failure of the Receiving Party to respond within such five business day period shall be deemed disapproval of the advertising materials in question. 5.4. Pulp and Paper Online Promotion. PaperExchange shall place the VerticalNet Links in a mutually agreeable location and size on the PaperExchange Site as soon as practicable and in no event more than 15 days after the Effective Date. The VerticalNet Links shall remain on the PaperExchange Site during the Term. 5.5. PaperExchange Home Page Promotion. VerticalNet shall place the PaperExchange Links on Pulp and Paper Online in a mutually agreeable location and size as soon as practicable and in no event more than 15 days after the Effective Date. The PaperExchange Links shall remain on Pulp and Paper Online during the Term. 5.6. Newsletter. VerticalNet shall include a PaperExchange Link in a mutually agreeable location and size in the Pulp and Paper Online weekly online newsletter sent to VerticalNet's newsletter database. 5.7. Discussion Groups. VerticalNet, in its reasonable business discretion, shall provide to PaperExchange co-sponsorship opportunities for discussion groups and USENET forums. 5.8. Non-Competition. 8 5.8.1. During the Term and for a period of four years after the termination of this Agreement, VerticalNet shall not, directly or indirectly, by itself, through its Affiliates or through any type of joint venture or similar affiliation with a third party, without prior written approval from PaperExchange, buy, sell or trade (a) paper pulp products through exchanges, auctions, or reverse auctions or any other e-commerce medium, (b) paper (other than finished paper-based products, including, but not limited to, books, stamps and labels) and copy paper (i) through exchanges, auctions or reverse auctions or (ii) in quantities greater than one ton through any e-commerce medium, (c) raw materials used to make paper packaging, including, but not limited to, linerboard, medium, other containerboard grades and corrugated sheet through exchanges, auctions, reverse auctions or any other e-commerce medium, or (d) paper rolls and reels weighing more than 50 pounds used by printers through exchanges, auctions, reverse auctions or any other e-commerce medium; provided, however, that this Section 5.8.1 [Non-Competition] shall not apply to advertisements, Storefronts or similar features on VerticalNet's Sites. 5.8.2. During the Term, VerticalNet will not, directly or indirectly, design, host, operate, maintain or otherwise participate in a co-branded career center or a co-branded
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Extract the exact clause related to "Parties" from the excerpt above.