The author lists كِلَا and كِلْتَا with an explicit condition: مُضَافَيْنِ إِلَى ضَمِيرٍ, meaning each is annexed to a pronoun.
كِلَاهُمَا: both of the two males/masculine referents.
كِلْتَاهُمَا: both of the two females/feminine referents.
Important: This dual-like case rule does not apply indiscriminately to every use of kilā/kiltā: annexation to a pronoun matters.
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Noun Case Classes: Type 5 — The Dual and Related Forms
The author lists كِلَا and كِلْتَا with an explicit condition: مُضَافَيْنِ إِلَى ضَمِيرٍ, meaning each is annexed to a pronoun.
كِلَاهُمَا: both of the two males/masculine referents.
كِلْتَاهُمَا: both of the two females/feminine referents.
Important: This dual-like case rule does not apply indiscriminately to every use of kilā/kiltā: annexation to a pronoun matters.