, 1990a, Introduction one: Simmel as a puzzling figure, in M. Kaern, B. S. Phillips & R. S. Cohen (eds.), Georg Simmel and contemporary sociology, Dordrecht, Springer, pp. 1-8.
, 1990b, The world as human construction, in M. Kaern, B. S. Phillips & R. S. Cohen (eds.), Georg Simmel and contemporary sociology, Dordrecht, Springer, pp. 75-98.
with Phillips, B. S. , Cohen, R.S. (eds) , 1990a, Georg Simmel and contemporary sociology, Springer, Dordrecht.