@book { CategorizationandL2VocabularyLearning,
    title = "Categorization and L2 Vocabulary Learning",
    author = "Xiaoyan {Xia}",
    year = "2014",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-03891-0",
    url = "https://www.peterlang.com/document/1048313"
}