WIA GC/1902/417 | Sponsel, Jean Louis to Warburg, Aby 12/01/1902 | on how to deal with 'the gentlemen' [the publishers], on cases of going to court, of issuing... |
WIA GC/1902/418 | Sponsel, Jean Louis to Warburg, Aby 31/01/1902 | wants information on how Warburg dealt with [Hermann Seemann Nachfolger] |
WIA GC/1905/567 | Sponsel, Jean Louis to Warburg, Aby 10/02/1905 | replies to a query on three Baccio Baldini engravings |
WIA GC/1905/568 | Sponsel, Jean Louis to Warburg, Aby 15/03/1905 | sends under separate cover the photograph of one Baldini engraving; he cannot find a 'Hosenkampf... |
WIA GC/1905/569 | Sponsel, Jean Louis to Warburg, Aby 23/03/1905 | they have found an engraving of 'Hosenkampf' and they are going to send him a photograph |