The provided links refer to the XML Linking Language (XLink), which is a standard developed by the World Wide Web Consortium (W3C) for creating hyperlinks in XML documents. XLink allows for more complex linking structures than traditional HTML links, enabling the creation of links that can point to multiple resources, have multiple endpoints, and include additional metadata. This standard is particularly useful for applications that require rich linking capabilities, such as in web services, document management systems, and data integration scenarios. XLink supports both simple and extended links, allowing developers to define the nature of the relationship between linked resources. The specification outlines the syntax and semantics of XLink, providing guidelines for implementation in XML-based applications.