In 2012 Ergo Pers will publish Giotto's hemel (Giotto's heaven), a livre de peintre with poetry by Stefan Hertmans and etchings by the Flemish painter and draftsman Karel Dierickx. Dierickx created a series of etchings inspired by early Renaissance sinopia drawings, in response to Hertmans' poems about Giotto, Piero della Francesca, Luca Signorelli and Fra Angelico.
° A sinopia is the preliminary sketch found on a layer of its own on the wall underneath the fresco. Sinopie are made with reddish, greenish or brownish earth colour, brushed on the arriccio layer, over which the intonaco is applied before painting. Sinopia takes its name from Sinop, a cape and port town on Turkey's Black Sea coast.