@book{
title = {Das Zahlenbuch 1 },
author = {Wittmann, Erich Ch.},
editor = {Herbst, Marta},
editor = {Müller, Gerhard N.},
editor = {998053045308896 - Das Zahlenbuch - Bd. 1 -  },
editor = {Rilegato a spirale },
year = {2005},
address = {Leipzig },
publisher = {Klett},
}