https://linguistics.osu.edu/about-us/osu-dissertations-linguistics (beliebiger Volltext)
https://linguistics.osu.edu/sites/linguistics.osu.edu/files/Parkinson_dissertation_1996.pdf (beliebiger Volltext)
Parkinson, F. B. (1996). The representation of vowel height in phonology. PhD Thesis, Ohio State Univ., [Columbus].