All six referent classes in the book are:
1. Masculine singular: ذَا.
2. Feminine singular: تَا / تِي / ذِي and variants.
3. Masculine dual: ذَانِ / ذَيْنِ.
4. Feminine dual: تَانِ / تَيْنِ.
5. Masculine plural: أُولَاءِ.
6. Feminine plural: أُولَاءِ.
“Five expressions” refers to core families, not every written variant.