Spon, J. S. d. History of the Barons de Spon, Comtes zu Forbach, and allied families (1978) (Lithogr.). Priv. produced.
Chicago-viite (17. p.)Spon, John Seymour de. History of the Barons De Spon, Comtes Zu Forbach, and Allied Families (1978). Lithogr. London: Priv. produced.
MLA-viite (8. p.)Spon, John Seymour de. History of the Barons De Spon, Comtes Zu Forbach, and Allied Families (1978). Lithogr. Priv. produced.
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