The "Dodo-Postcards" watermark is NOT on the actual card – it is an online watermark only.
Vienna. The Opera House. H. D. H. Hubmann
Vienna. The Opera House. C. Bauer. Nr. 454
Vienna. The Opera House. Rau Color. Hans H. Rau. Multi View
Vienna. The Opera House. Hans H. Rau
Vienna. The Opera House. A. Kellner. 1969
Vienna. The Opera House by Night. Bauer. Nr. 445. 1999
Vienna. The Opera House by Night. Bauer. 1998
