//-->
Mathematik für Wirtschaftswissenschaftler : problemorientierte Einführung
Karmann, Alexander, (2000)
Mathematical methods for economics
Klein, Michael W., (2002)
Karmann, Alexander, (2003)
On a shortened method of estimation of mental factors by regression
Ledermann, Walter, (1939)
Some mathematical remarks concerning boundary conditions in the factorial analysis of ability
Ledermann, Walter, (1936)
Handbook of applicable mathematics
Ledermann, Walter,