@book{
title = {Arbeitsheft},
author = {},
editor = {Gerber, Monika},
editor = {998048356608896 - Modernes Russisch Okno 2 - 3 -  },
editor = {Tit dalla cop },
editor = {Nome degli A. dalla 2. di cop },
year = {2007},
edition = {2. ed},
address = {Stuttgart [etc.] },
publisher = {Klett},
}