@book { Introduccinalasvariedadeslingsticasdelespaol,
    title = "Introducción a las variedades lingüísticas del español",
    author = "Alex {Quintanilla}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "New York, United States of America",
    doi = "10.3726/b16716",
    url = "https://www.peterlang.com/document/1063331"
}