Hoffman, O. “Present-Day Achievements in the Environment Sociology, A Simpozion on Wondschoten, Holland, June 17-20, 1992”. Sociologie Românească, Vol. 4, no. 2, Feb. 2013, pp. 241-5, https://revistasociologieromaneasca.ro/sr/article/view/1993_2_hoffman_oscar.