Daniel-Erasmus Kahn: Die deutschen Staatsgrenzen: rechtshistorische Grundlagen und offene Rechtsfragen ("The German national borders: legal-historical foundations and open legal questions"). Oxford University Press, 2004. ISBN 9783161484032. Teoksen verkkoversio.(saksaksi)
Stephen R. Graubard, (ed.).Exit from Communism. Transaction Publishers, 1993. Pp. 153–154. [1]
buffalo.edu
ontology.buffalo.edu
Smith, Barry. "Fiat Objects" (PDF). Department of Philosophy, Center for Cognitive Science and NCGIA, SUNY at Buffalo (NY): 24–25. Retrieved 2.6.2013