Agendamagazine.be.
'Think in Colour' itself is actually engaged in designing. The book anthologises 32 years of hard work and experiments at the same time. The colours inside the book evolve just like the colours on the cover. Page by page, the yellow morphs into orange, and then brown, bordeaux, bright red, pink, blue… Think in Colour does not transform harmoniously. The colours on one page run onto the next. They overlap, clash, and collide."
http://www.agendamagazine.be/en/blog/hugo-puttaert-think-colour