Sozialer Fortschritt, Vol. 67 (2018), Iss. 4 : pp. 269–282 | First published online: May 10, 2018
Vierteljahrshefte zur Wirtschaftsforschung, Vol. 86 (2017), Iss. 3 : pp. 97–102 | First published online: June 14, 2018
