ComrieB (2018) The world’s major languages, 3rd ed.New York, NY: Routledge. ISBN: 9780367580711.
2.
GarraffaMSoraceAVenderM (2023) Bilingualism Matters: Language Learning Across the Lifespan. Cambridge, UK: Cambridge University Press. ISBN: 9781009333375.
3.
KohnertK (2013) Language disorders in bilingual children and adults, 2nd ed. San Diego, CA: Plural Publishing. ISBN: 978-1-59756-534-9.