Alvar Aalto (Finnish, 1898-1976), pair of tank armchairs, model 400, designed 1936, manufactured by Artek, black finish birch frame with black and white 'Zebra' pattern upholstery (2), height 65 cm, labels: Markku Lahti, Alvar Aalto: designer, p. 174, Alvar & Aino Aalto design: Bischofberger collection, Kellein, p. 128-129