@Book{RANFE2009008464, title = "Qualitative analyse und ihre wissenschaftliche bergr\"{u}ndung", author = "B\"{o}ttger, Wilhelm", publisher = "Leipzig : Wilhelm Engelmann", editor = "Wilhelm Engelmann", URL = "http://bibliotecavirtual.ranf.com/i18n/consulta/registro.do?id=8464", year = "1925", }