"In
1969, the publisher Robert Laffont launched the literary equivalent of
Prospective 21e Siècle: the imprint Ailleurs et Demain - Elsewhere and Tomorrow, in English - dedicated to science
fiction and under the direction of Gérard Klein. Over the coming years Ailleurs
et Demain would publish translations of works by giants of the genre such as
Philip K. Dick, John Brunner, Frank Herbert, and Arthur C. Clarke along with
novels by French s.f. writers like Jacques Sternberg, Michel Jeury, and Klein
himself . Klein was an admirer of the
Prospective series and decided to package A & D fiction using the same
process, called Héliophore and originally developed in the 1930s by Louis Defay
to transform aluminum paper for printing.
Some of the Ailleurs Et Demain designs closely resemble specific Prospective
21e Siecle sleeves, while others are new but clearly inspired by the series.
(With both the albums and the novels, nobody seems to know the identity of the
designers, who were in-house and uncredited).
The design style, which eventually extended beyond silver to gold and
copper book covers, was maintained for over 20 years, before being abandoned"
-- from my essay "This Was Tomorrow", published 2014