I found this fantastic portfolio filled with 30 prints of pencil drawings. They are Art Decó interiors from Vienna, my guess is early 1930s, all signed LD.
I appreciate any help with my research here:) Who was LD? Was it an artist of the "Wiener Werkstätte"? The folder states "Moderne Wiener Möbel" on a sticker of an art book store in Barcelona of that period. Click on the images to enlarge: