@book { ReichmitETFsDie4SulendesInvestierens,
    title = "Reich mit ETFs – Die 4 Säulen des Investierens",
    author = "Alex {Grabing}",
    year = "2024",
    publisher = "via tolino media",
    address = "München, Deutschland",
    url = "https://tolino.openpublishing.com/document/1457933"
}