F/B: front/back harmony
R|T: rounding, total harmony
—: not applicable

Erzya

/o/ : /e/ (difference in rounding)

Hungarian

F/B harmony: /ɑː/ : /eː/, /o/ : /ɛ/ (difference in height), /ɒ/ : /ɛ/ (difference in rounding – which can be analyzed as phonetic, not phonological). Rounding harmony:  /ɛ/ : /ø/ (difference in height)

Nganasan

In addition to the fact that /u̯ɑ/, although it belongs to the rounded class of vowels, is phonetically unrounded, all of its actual alternations (and almost all of those of /u̯ɑ/) are non-potential, since they alternate with high vowels, and some of these alternations are monophthong : diphthong alternations (i : ɑ,  ɨ : ɑ, i : u̯ɑ,  ɨ : u̯ɑ, i̯ɑ : ɑ).