T. W. Knight, “Languages of designs: from known to new,” Environment and Planning B 8 (1981): 213- 238; T. W. Knight, “Transformations of languages of designs,” Environment and Planning B 10 (1983): Part 1 125-128, Part 2: 129-154, Part 3:155-177; T. W. Knight, Transformations in Design (Cambridge University Press, Cambridge, 1994.