Select Element by attribute value and order by element value in CSharp

using System;//w  ww.ja v a  2 s.  co m
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Xml;
using System.Xml.Linq;
public class MainClass {
    public static void Main() {
        XDocument xDocument = new XDocument(
          new XElement("Books",
            new XElement("Book",
              new XAttribute("type", "Author"),
              new XElement("FirstName", "A"),
              new XElement("LastName", "B")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "C"),
             new XElement("LastName", "D"))));

        IEnumerable<XElement> elements =
              from e in xDocument.Descendants("Book")
              where ((string)e.Attribute("type")) != "Author"
              orderby ((string)e.Element("LastName"))
              select e;

        foreach (XElement element in elements) {
            Console.WriteLine("Element: {0} : value = {1}",element.Name, element.Value);
        }
    }
}