Phonemically, Shuangfeng dialect has three tones. Phonetically, however, the pitch of a syllable depends on the voicing of the initial consonant so the tones are counted as five:
Coblin, W. South. (2011). Comparative Phonology of the Central Xiāng Dialects. Taipei: Institute of Linguistics, Academia Sinica.
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Wu, Yunji. (2005). A Synchronic and diachronic study of the grammar of the Chinese Xiang dialects. Berlin, New York: Mouton de Gruyter. ISBN 3-11-018366-8