You might like Left Right Orange Matrices Gordon House 1967 Red Matrices Gordon House 1967 4 Red Arcs Gordon House 1967 Series 40cm Continued I Gordon House 1969 Triangle A Gordon House 1971 Triangle B Gordon House 1971 Triangle D Gordon House 1971 Triangle E Gordon House 1971 Triangle F Gordon House 1971 Triangle G Gordon House 1971 Amsterdam B Gordon House 1971 Amsterdam A Gordon House 1971