Get ListItems using SharePoint Services

Get ListItems with there columns of a specific SharePoint List 
using the SharePoint Webservice Lists.asmx .  

    private XmlNode GetSiteListItems(string sSiteUrl, string sSiteList)
    {
        WS_Lists.Lists list = new WS_Lists.Lists();
        list.Url = sSiteUrl + "/_vti_bin/lists.asmx";
        if (bDefaultLogon)
            list.Credentials = System.Net.CredentialCache.DefaultCredentials;
        else
        {
            list.PreAuthenticate = true;
            list.Credentials = new System.Net.NetworkCredential(sTechnicalUser, sTechnicalPw, sDomain);
        }
        Console.WriteLine(sSpaces + "Start GetSiteListItems " + sSiteList + " " + sSiteList + "...");
        string rowLimit = "99999";
        XmlDocument xmlDoc = new System.Xml.XmlDocument();
        XmlNode listQuery = xmlDoc.CreateNode(XmlNodeType.Element, "Query", "");
        XmlNode listViewFields = xmlDoc.CreateNode(XmlNodeType.Element, "ViewFields", "");
        listViewFields.InnerXml = "<FieldRef Name=\"Title\">" +
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME1\"></FieldRef>" + 
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME2\"></FieldRef>" +
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME3\"></FieldRef>" +
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME4\"></FieldRef>" +
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME5\"></FieldRef>" +
                                  "<FieldRef Name=\"INTERNAL_FIELDNAME6\"></FieldRef>" ;
          
        XmlNode listQueryOptions = xmlDoc.CreateNode(XmlNodeType.Element, "QueryOptions", "");
        XmlNode ndListItems = null;
        try
        {
            ndListItems = list.GetListItems(sSiteList, null, listQuery, listViewFields, rowLimit, listQueryOptions, null);
        }
        catch (Exception e)
        {
            Console.WriteLine(sSpaces + "Error GetSiteListItems {0}", e.Message);
        }
        finally
        {
            list.Dispose();
            Console.WriteLine(sSpaces + "End GetSiteListItems " + sSiteList + " " + sSiteList);
        }
         return ndListItems;
    }