-
Johann Helfgen was a
German politician. He was born in
Dudweiler on May 9, 1887.
Helfgen did
military service 1907-1909, and
fought in the
First World...
- Bibcode:1998AeST....2..425S. doi:10.1016/s1270-9638(99)80002-9. ISSN 1270-9638.
Helfgen, B.; Türk, M.; Schaber, K. (2003). "Hydrodynamic and
aerosol modelling...