Article: "Major search engines improve Sitemaps protocol" by Juan Carlos Perez. Explains how Google, Yahoo and Microsoft have enhanced the Sitemap by allowing robots.txt files to indicate the location of the Sitemap file. It was also announced that Ask.com will support the protocol and IBM has also signed up to support the effort.

Article: "Use Sitemap Standards to Help Search Engines" by Tony Patton. Explains what a Sitemap is, the need for a Sitemap standard, how to create a Sitemap with tools and generators, and how to notify a search engine.

Article: "Search Engines Unite on Unified Sitemaps Systems" by Danny Sullivan. Discusses the support of unified Sitemaps, how Sitemaps work, and how to submit Sitemap files to Google Webmaster Central, Microsoft Live Search and Yahoo Site Explorer.

Article: "Google, Yahoo and Microsoft Agree to Standard Sitemaps Protocol" by Marshall Kirkpatrick. Explains the collaboration between the companies to start using the same Sitemaps protocol to index sites.

Article: "Google, Microsoft and Yahoo as Partners?" by David Needle. This article explains how these companies announced support for Sitemaps 0.90, a free, unified format for publishers and Webmasters to submit their content to search engines.

Article: "Major Search Engines Unite to Support a Common Mechanism for Website Submission." This article explains how a new Sitemaps protocol will enable Google, Yahoo and Microsoft to provide more comprehensive and fresh search results.