Structures

Ackoff, Russell L. and Fred E. Emery
[1972]  On Purposeful Systems, Tavistock Publications, London

Kepes, Gyorgy  editor
[1965]  Structure in Art and in Science, Studio Vista, London

Nadel, Siegfried Frederick
[1957]  The Theory of Social Structure, Cohen & West, London, 1962

Piaget, Jean
[1968, French Edition]  Structuralism, Routledge & Kegan Paul, London, 1971
Original Title: Le Structuralisme, Presses Universitaires de France, Paris, 1968