The IPA provides two letters for reduced vowels: low/open ⟨ɐ⟩ and mid ⟨ə⟩. These are not defined for rounding. For languages such as English, French and Russian that have additional or just different reduced vowels, some sources use the non-IPA letters ⟨ᵿ⟩ and ⟨ᵻ⟩ for high/close rounded and unrounded reduced vowels, or redefine IPA ⟨ɵ⟩ as a rounded reduced mid vowel.
