@book { GrazingAbnehmenmit7SnacksproTag,
    title = "Grazing: Abnehmen mit 7 Snacks pro Tag",
    author = "Heike {van Braak}",
    year = "2015",
    publisher = "Open Publishing",
    address = "München, Deutschland",
    url = "https://books.openpublishing.com/document/288860"
}