Looking for further information on the person buried in Lake Madison Luthern Cemetery listed as: Gilbert N. Oppen who died 25th September 1892. Believe this Man to be the Father of Gilbert Oppen nee Gunnar Oppi. Gilbert N. believed to be Gulbrand Nilsen Oppi. Lived with his brother Ole in Lake Madison South Dakota. Anyone finding information regarding Gilbert N. Oppen please forward to me and I would be very grateful. Thank You.