@book { ProductRecommendationsinECommerceRetailingApplications,
    title = "Product Recommendations in E-Commerce Retailing Applications",
    author = "Nicolas {Knotzer}",
    year = "2018",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b13971",
    url = "https://www.peterlang.com/document/1068515"
}