GIACOMO BALLA (Torino 1871 - Roma 1958) Linea Forza 1920s - from a sketch of 1917 tempera and pencil on cardboard 21.5x25.9 cm signed Futur Balla on the lower side on the reverse inscribed "LINEE FORZE BALLA" and stamp "Pugno di Boccioni" on the reverse label exhibition Balla. Inventore, mago, profeta.   The artwork has a certificate released by Archivio Gigli, Rome. The artwork is registered at Archivio Gigli serie 2013 n. 551. The artwork has a certificate of authenticity released by Luce Balla.   Provenance Casa Balla, Rome Sotheby's London, 1980 Private collection   Exhibited Balla. Inventore, mago, profeta. (curated by Elena Gigli), Azimut, Roma, 1 - 31 October 2013   Literature Arch. Fut., II, 1962, n. 29li G. Lista, Balla, Edizioni Galleria Fonte d'Abisso, Modena, 1982, n. 603, pp. 291 (ill. b/n), 520