"P. Soyer: Portrait Of Baron E. De S. De Friedberg, (ink)"
In the 1880s, the publication of the illustrated catalog of the SAF required artists to send a drawing of the painting they wanted to exhibit, so that an engraver could transfer this drawing to the catalog. The drawing presented is autograph executed by the painter from his painting. It would seem that Baron Friedberg was a deputy, the portrait was exhibited at the 1881 salon The sheet of the drawing has been folded and we can read in the lower right margin: "nature" 
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