@book { Peticionesenalemnyespaol,
    title = "Peticiones en alemán y español",
    author = "Pau {Bertomeu Pi}",
    year = "2022",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b19223",
    url = "https://www.peterlang.com/document/1170958"
}