无法使用Open XML SDK创建文档

我正在学习将Open XML SDK与Visual Studio Community 2015一起使用。我试图通过以下示例创建一个文档：https://msdn.microsoft.com/en-us/library/dd440953（v=office.12）.aspx

我的代码：

using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Wordprocessing;
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
          Program p = new Program();
          p.HelloWorld("abc.docx");
        }
        public void HelloWorld(string docName)
        {
            // Create a Wordprocessing document. 
            using (WordprocessingDocument package = WordprocessingDocument.Create(docName, WordprocessingDocumentType.Document))
            {
                // Add a new main document part. 
                package.AddMainDocumentPart();
                // Create the Document DOM. 
                package.MainDocumentPart.Document =
                  new Document(
                    new Body(
                      new Paragraph(
                        new Run(
                          new Text("Hello World!")))));
                // Save changes to the main document part. 
                package.MainDocumentPart.Document.Save();
            }
        }
    }
}

我在WordprocessingDocument.Create:上出错

Error   CS0012  The type 'Package' is defined in an assembly that is not referenced. 
You must add a reference to assembly 'WindowsBase, Version=4.0.0.0, Culture=neutral, PublicKeyToken=1234'.  
ConsoleApplication1 c:'users'john'documents'visual studio 2015'Projects'ConsoleApplication1'ConsoleApplication1'Program.cs

我已经安装了带有nuget 的DocumentFormat.OpenXml软件包

代码出了什么问题？