I am looking for information on my great-grandfather, Fred Groff. He was born in 1876 in Amsterdam, Holland and emigrated to the US about 1888 and was naturalized. His father's name is listed as Joseph Groff on his death certificate. He had two brothers listed in his obituary. He married Effie Mae Jennings in Durant, Bryan, Oklahoma and had five children, one of which was my grandmother. He died December 27, 1961 in Edmond, Oklahoma. Any information would be greatly appreciated. Thank you!