类型或命名空间名称'WorkbookEngine'找不到(您是否缺少using指令或程序集引用?)

我用这个代码片段从数据集创建一个excel表格(我解析。rtf文件并得到一个数据集列表)。但是我得到错误与第3行我的代码片段

错误:找不到类型或命名空间名称"WorkbookEngine"(您是否缺少using指令或汇编引用?)

XmlDataDocument xmlDataDoc = new XmlDataDocument(DS);
XslCompiledTransform xt = new XslCompiledTransform();
StreamReader reader = new StreamReader(typeof(WorkbookEngine).Assembly.GetManifestResourceStream(typeof(WorkbookEngine), "ValidationReport1.xls"));
XmlTextReader xRdr = new XmlTextReader(reader);
xt.Load(xRdr, null, null);
StringWriter sw = new StringWriter();
xt.Transform(xmlDataDoc, null, sw, null);
StreamWriter myWriter = new StreamWriter(System.Windows.Forms.Application.StartupPath + "''Reports''ValidationReport1.xls");
myWriter.Write(sw.ToString());
myWriter.Close();