@book { ReconsideringEarlyBilingualism,
    title = "Reconsidering Early Bilingualism",
    author = "Marcin {Opacki}",
    year = "2017",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-07250-1",
    url = "https://www.peterlang.com/document/1050673"
}