Interferensi bunyi vokal [c], [o:], [oe], dan [ф:] dalam bahasa Jerman oleh pembelajar bahasa Jerman berbahasa ibu bahasa Jawa: sebuah studi kasus pada siswa kelas XII jurusan bahasa SMA N 1 Sukoharjo angkatan 2008 = Interference of vowel pronunciation on [c], [o:], [oe], and [ф:] in German by the German learner whose mother tongue are Javanese: in this essay, the informants are 12th grade students of language major study at SMAN 1 Sukoharjo in the academic year 2008