El monstruo Groppopol, c2005: t.p. (Sandra Siemens)

Lucía, no tardes, 2015: title page (Sandra Siemens) page 4 of cover (Sandra Siemens (1965); has published short stories and novels for children and youth for which she has receveived numerous distinctions, among which the premio El Barco de Vapor for her work La muralla)

La muralla, 2016: title page (Sandra Siemens) of cover

Biblioteca del congreso (Estados Unidos), 18 marzo 2020: Catálogo electrónico http://bit.ly/2WrkTJg