Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
between you and I, between he and his mother
Between is a preposition, and Standard English requires that its objects be in the accusative case, so these phrases should be between you and me, between him and his mother. Mistakes in the cases of pronouns occur most frequently in compound subject and compound object phrases like these; between us would almost never be confused with between we, unless the pronoun were part of a compound nominal, such as between the boys and we [should be us]. Standard English users enforce these case choices rigorously in both speech and writing; failures are shibboleths.
