@book{
title = {Elementarmathematik },
author = {Klein, Felix},
editor = {Blaschke, W.},
editor = {Born, M.},
editor = {Courant, R.},
editor = {Runge, C.},
editor = {Seyfarth, F.},
year = {2uuu},
address = {Berlin },
publisher = {J. Springer},
}