@book { AcousticsoftheVowel,
    title = "Acoustics of the Vowel",
    author = "Dieter {Maurer}",
    year = "2016",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    doi = "10.3726/978-3-0343-2391-8",
    url = "https://www.peterlang.com/document/1067698"
}