That Summer in Paris is a book by Morley Callaghan (1903–1990). In 1929, the Candian novelist “spent some months in Paris, where he was part of the great gathering of writers in Montparnasse that included Ernest Hemingway, Ezra Pound, Gertrude Stein, F. Scott Fitzgerald, and James Joyce.” [Wikipedia]
His “Memories of Tangled Friendships with Hemingway, Fitzgerald and Some Others” were published in 1963. This is the cover of Dell’s paperback (Laurel Edition 86649) from 1964, featuring all-caps Futura Black in the French national colors.