JENSEN, B. William R. Copeland: The Uneasy Alliance. Collaboration between the Finnish Opposition and the Russian Underground. 1899-1904. Suomalaisen Tiedeakatemian Toimituksia ser. B torn. 179. Helsinki, 1973. 224 s. FM 33. Historisk Tidsskrift, v. 13, 1 jan. 1978.