@book { DesignofaPortfolioManagementSystemforSoftwareLineDevelopmentMergingtheGapbetweenSoftwareProjectandProductManagement,
    title = "Design of a Portfolio Management System for Software Line Development: Merging the Gap between Software Project and Product Management",
    author = "Michael {Lang}",
    year = "2015",
    publisher = "Anchor Academic Publishing",
    address = "Hamburg, Germany",
    url = "https://m.anchor-publishing.com/document/312685"
}