 In his sculptural series "Relatum", each work consists of one or more light-colored round stones and dark, rectangular iron plates.From his first solo exhibition in Japan in 1967, Lee Ufan was invited by Manfred Schneckenburger to participate in Documenta VI (1977) in Kassel, and in 1969 and 1973 he represented Korea in the Bienal de São Paulo.His work was included in the 1992 Tate Liverpool exhibition, "Working With Nature