Evaluate the work of the artist F.Leonhardt.S
 

How can we evaluate the work of the artist F.Leonhardt.S. which was brought from Germany after the war - work not on canvas but on the board-type hardboard

kan, 1. By.
2. Material and equipment manufacturing (oil on canvas, paper, pastels, watercolors, lithographs, oil, pencil, etc.).
3. Size (horizontal x vertical for painting).
4. Creation Time (1899 /beg., Mid-twentieth century. Etc.).
5. Captions, labels, stamps, birochki (if any - need photos).
6. Condition (breakouts, talus, scrapes).
7. Expert opinion (if available) - the organization name of the expert.
8. Qualitative picture pictures back of the painting, photo captions (if any).
9. Origin of the picture.
10. Any other information useful for the attribution of paintings