How can I force XDocument to output “UTF-8” in the declaration line?

Question

The following code produces this output:

Answer 1

Allow me answer my own question, this seems to work:

private static string BuildXmlWithLINQ()
{
    XDocument xdoc = new XDocument
    (
        new XDeclaration("1.0", "utf-8", "yes"),
        new XElement("customers",
            new XElement("customer",
                new XElement("firstName", "Jim"),
                new XElement("lastName", "Smith")
            )
        )
    );
    return xdoc.Declaration.ToString() + Environment.NewLine + xdoc.ToString();
}