@book { MentaleFitnessimGolf,
    title = "Mentale Fitness im Golf",
    author = "Martin K. W. {Schweer}",
    year = "2017",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b11587",
    url = "https://www.peterlang.com/document/1055724"
}