@Work{OL1924849W,
    title: {Linear algebra},
    author: {John B. Fraleigh and Raymond A. Beauregard},
    first_publish_year: {1987}
}

@Author{OL230750A,
    name: {John B. Fraleigh},
    birth_date: {1930}
}
@Author{OL2030008A,
    name: {Raymond A. Beauregard},
    birth_date: {ca.1944}
}