Use System.Drawing class

Hi,
How can I to use System.Drawing.Bitmap class into athoer class?


using System.Data;
using System.Collections;
using System.Globalization;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.Globalization;
using System.Text;


namespace University
{
    public class Class1
    {
      System.Drawing.Bitmap BMP=new System.Drawing .Bitmap();
    }
}
when I use System.Drawing.Bitmap gives error this class does not exists !!!!!!!!

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