All M.C. Escher works © Cordon Art BV - Baarn - the Netherlands.
10 7/8 x 11 1/2 in (277 x 292 mm)
- M.C. Escher: His Life and Complete Graphic Work, Catalog 389
- Magic of M.C. Escher, Illustration 198
- José Martínez Aroza's Escher Gallery (as 'Relatividad')
Escher also executed Relativity as a woodcut.