@book { PaulValryetledessin,
    title = "Paul Valéry et le dessin",
    subtitle = "Préface de Martine Rouart",
    author = "Paul {Ryan}",
    year = "2007",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1103310"
}