https://www.econstor.eu/handle/10419/266654
https://www.econstor.eu/handle/10419/44755
https://www.econstor.eu/handle/10419/265745
https://www.econstor.eu/handle/10419/219786
https://www.econstor.eu/handle/10419/279382
https://www.econstor.eu/handle/10419/160973
https://www.econstor.eu/handle/10419/129551
https://www.econstor.eu/handle/10419/63220
https://www.econstor.eu/handle/10419/82723