's Nachts

's Nachts ("At Night," 1999), translated in German as Nachts, is a children's book written and illustrated by German author Wolf Erlbruch written for the Dutch Kinderboekenweek, an annual event promoting children's literature.

It is a story about a boy, Fons, who, unable to sleep, drags his father on a walk through town and encounters the most fantastic animals and creatures.

[1] For his mixed-media illustrations in Nachts, Erlbruch used cut-outs from stacks of papers from 1940s German wallpaper and other eclectic sources.

Each page features a moon, and some of those were cut from plans from a French company for a railroad in China; the mathematical formulas, explained Erlbruch, represent the adult, rational world—cutting up papers with such calculations on it he suspects is an act of rebellion.

[1] The Dutch daily newspaper Trouw wrote that in Nachts, Erlbruch "cuts, pastes, draws, paints, and writes a beautiful little piece of art.