Complex sentence: This supposed painting of Yates, at this time, cannot be verifed though it is strongly believed that it exists at either the Smithsonian in Washington D.C., somewhere in Kingston, New York, or at the Schenectady County Historical Society.
Split into simpler sentences: This supposed painting of Yates, at this time, cannot be verifed though it is strongly believed that it exists. At either the Smithsonian in Washington D.C., somewhere in Kingston, New York, or at the Schenectady County Historical Society.