It is the Quechua variety used by the Academia Mayor de la Lengua Quechua in Cuzco, which also prefers the Spanish-based five-vowel alphabet.
[2] On the other hand, the official alphabet used by the ministry of education has only three vowels.
[3] There is debate about whether Cuzco Quechua has five /a, e, i, o, u/ or three vowel phonemes: /a, ɪ, ʊ/.
[4] While historically Proto-Quechua clearly had just three vowel phonemes /*a, *ɪ, *ʊ/, and although some other Quechua varieties have an increased number of vowels as a result of phonological vowel length emergence or of monophthongization, the current debate about the Cuzco variety seems to be not phonological in matter but just orthographic.
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