(Interior art for the 1975 French OPTA edition of The Death of Grass (1956) and The Long Winter (1962), John Christopher)
I cannot ascertain the identity of Cathy Millet. There is a well known Catherine Millet—a French writer, art critic, curator, etc. However, I do not think they are the same. If you know more information about who she might be, please please please let me know! (French articles are fine — I can read them easily).
Cathy Millet created a handful of covers and larger number of interior illustrations for the French publisher OPTA. Here’s her incomplete isfdb.org listing which I used as a jumping off point. The ones which caught my eye are her spectacular interior illustrations for two John Christopher post-apocalyptic Continue reading Adventures in Science Fiction Cover Art: Cathy Millet illustrates Michael Moorcock, Bob Shaw, and John Cristopher