釋氏要覽 2.330

2.330

界者何義。瑜伽論云。種性義。因義。住持義。婆沙論云。分叚義。聲論云。趣義（俱舍論云）。種族義。因果不同。故有三焉。

What is the meaning of 'realm' (dhātu)? The Yogācārabhūmi-śāstra says: 'It has the meaning of lineage (gotra), the meaning of cause, and the meaning of upholding.' The Vibhāṣā-śāstra says: 'It has the meaning of distinct sections.' The Treatise on Sound says: 'It has the meaning of destiny.' The Abhidharmakośa-śāstra says: 'It has the meaning of category (species).' Because their causes and effects are not the same, there are three of them.