1
by Welfens, Paul J. J., Graack, Cornelius
Published 1996
Springer Berlin Heidelberg

3
by Welfens, Paul J. J., Jungmittag, Andre
Published 2002
Springer Berlin Heidelberg

5
by Welfens, Paul J. J., Audretsch, David B., Addison, John T., Grupp, Hariolf
Published 1998
Springer Berlin Heidelberg

6
by Welfens, Paul J. J.
Published 1999
Springer Berlin Heidelberg

7
by Welfens, Paul J. J.
Published 1997
Springer Berlin Heidelberg

8
by Welfens, Paul J. J.
Published 1988
Physica-Verlag HD