Hi, 

I'm currently reading a book, The Spiral Shell, a memoire by Sandell Morse about Jews in France during WWII...how some were hidden, how some resisted, about some organizations which helped, etc. Although the book is not about Nice, perhaps you may find it of interest and it may provide some additional resources to you.

All the best! 
--
Karen Calmon Lukeman
KALMANOWITZ (Lyubcha and towns near Grodno, Vilna and Minsk)
GOLDSMITH (Bakshty and Ivje)
NASSER (Damascus)
BENBAJI (Damascus)
BALLAS (Damascus)