MEXICO. Lot (4 Bücher): Davon zwei Auktionskataloge: David Feldman- All World Collections & Large Lots Select Single Lots/ Mexico Specialised (Geneva 2010); Sothevy's- The Erich Koenig Collection of the 19. and 20. Century Stamps and Covers of Mexico (New York 1995); Hartmann, R., Märkte im alten Peru, Bonn 1968 (Disertation); Schmitz, o. Die Finanzen Mexikos. Leipzig 1894.