The second purusa, Garbhodakasayi Visnu, is an expansion of Pradyumna; and the third purusa, Ksirodakasayi Visnu, is an expansion of Aniruddha. All these are within the category of manifestations of Narayana, who is a manifestation of Sri Krsna

Expressions researched:
"the second puruṣa, Garbhodakaśāyī Viṣṇu, is an expansion of Pradyumna; and the third puruṣa, Kṣīrodakaśāyī Viṣṇu, is an expansion of Aniruddha. All these are within the category of manifestations of Nārāyaṇa, who is a manifestation of Śrī Kṛṣṇa"

CC Adi-lila

The first puruṣa-avatāra, Mahā-Viṣṇu in the Causal Ocean, who is the creator of the aggregate material energy, is an expansion of Saṅkarṣaṇa; the second puruṣa, Garbhodakaśāyī Viṣṇu, is an expansion of Pradyumna; and the third puruṣa, Kṣīrodakaśāyī Viṣṇu, is an expansion of Aniruddha. All these are within the category of manifestations of Nārāyaṇa, who is a manifestation of Śrī Kṛṣṇa.

CC Adi 2.56, Translation and Purport:

“You are the ultimate shelter of these three plenary portions. Thus there is not the slightest doubt that You are the primeval Nārāyaṇa.

Brahmā has confirmed that Lord Kṛṣṇa is the Supreme, the source of the three manifestations known as Kṣīrodakaśāyī Viṣṇu, Garbhodakaśāyī Viṣṇu and Kāraṇodakaśāyī Viṣṇu (Mahā-Viṣṇu). For His pastimes, Lord Kṛṣṇa has four original manifestations—namely Vāsudeva, Saṅkarṣaṇa, Pradyumna and Aniruddha. The first puruṣa-avatāra, Mahā-Viṣṇu in the Causal Ocean, who is the creator of the aggregate material energy, is an expansion of Saṅkarṣaṇa; the second puruṣa, Garbhodakaśāyī Viṣṇu, is an expansion of Pradyumna; and the third puruṣa, Kṣīrodakaśāyī Viṣṇu, is an expansion of Aniruddha. All these are within the category of manifestations of Nārāyaṇa, who is a manifestation of Śrī Kṛṣṇa.