Declensions.—There are three declensions, which are named from the stems to which the case endings are attached.
1. First or Â-declension, with stems in α_) Vowel Declension.
2. Second or O-declension, with stems in ο)
3. Third or Consonant declension, with stems in a consonant or in ι and υ.
The nominative and accusative are alike in the singular and plural of all neuter nouns. The nominative and vocative are alike in the plural.
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].