Letters: to M. V. Hay with reference to the various sources of information about the Duc De Montpelier Letters from Miss B. F. Hislop, New York; Madame de Castillon du Perron, Paris; the Curator of Messrs Coutts & Co.'s museum, and Keeper of the Archives, London; Antoine de Halasz, Paris, and Denise Lyon, Conservator of the Bibliotheque Nationale, Paris, to M. V. Hay with reference to the various sources of information about the Duc De Montpelier. August 1957 - 1958