unknown signature

Looks good to my eye. Biographical information if you haven't already found it.

https://lessonnos.art/fr/yvonne-de-sonneville

Debora

 

thanks

 

That's classified

 

If you want information on a 100 year old painting and you consider it private, why are you asking on a public forum? Any answer you get here will be incomplete because they are basing their guesses on incomplete information so you can't be sure it's correct. This is just silly

 

You could contact the de Sonneville museum:
https://www.gradignan.fr/culture/musees/musee-de-sonneville-396.html
museesonneville@ville-gradignan.fr

 

The painting is of a friend of mine and he just wanted to know the signature and that is perfectly possible without seeing the painting itself. If you are a coneceur of signatures. And the painting is not 100 years old but was in the familly for 100 years where my friend bought it from. But it is oke, he will try to seek an expert. My apologies for the shady way of asking info. All is fine no regreds.