@book { EinsamkeitvonSenioreninSeniorenheimen,
    title = "Einsamkeit von Senioren in Seniorenheimen",
    author = "",
    year = "2005",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783638409896",
    url = "https://www.hausarbeiten.de/document/43116"
}