

रोहिणीतनयो रामोऽकाराक्षरसम्भवः । तैजसात्मकः प्रद्युम्न उकाराक्षरसम्भवः ।। १८४ ॥ प्राज्ञात्मकोऽनिरुद्धो वै मकाराक्षरसम्भवः । अर्धमात्रात्मकः कृष्णो यस्मिन् विश्वं प्रतिष्ठितम् ।। १८५ ।। इति ।

Balarama, the son of Rohini, [who is the predominating deity of the waking state (viśva),] has arisen from the letter a; Pradyumna, who is the predominating deity of the drēam state (taijasa), has appeared from the letter u; Aniruddha, who is then witness of the state of deep sleep (prājña), is born of the letter m; and Krsna, [who transcends the three states,] in whom this cosmos is situated, embodies the half syllable [i.e., nāda]. (Gopala-tapani Upanishad 2.55-56)

The Gopala-tapani Upanishad mantra mentions the four members of the catur vyuha in terms of the viśva, taijasa, and prājña, but not the waking, drēam, and deep sleep states.

Here, the purpose is not that. Just as Supreme Personal Absolute Kṛṣṇa manifests as the catur vyha, so also the sonic vibration Om, which symbolizes Krsna, envelops within its layered dimensions the catur-vyuha. This is what the Gopāla-tāpanī mantra signifies. The purpose is to indicate that Ultimate Reality is a single nondual substance, but also containing inherent variety.

Accompanied by His three [expansions], Rāma, Aniruddha, and Pradyumna, the omnipotent Bhagavān Kṛṣņa resides there [in Mathurā], along with His potency, Rukmini. ( Gopala-tapani Upanishad 2.40)

This is also seen in Bhagavatam.

ओ नमो भगवते तुभ्यं वासुदेवाय धीमहि । प्रद्युम्रायानिरुद्धाय नमः सङ्कर्षणाय च ॥ १०६ ॥ इति मूर्त्यभिधानेन मन्त्रमूर्तिममूर्तिकम् । यजते यज्ञपुरुषं स सम्यग्दर्शनः पुमान् ॥ १०७ ॥ इति ।

Obeisance unto You, O Bhagavan Vasudeva. We meditate upon You. Obeisance also unto Pradyumna, Aniruddha, and Sankarsana. One who thus worships the Master of Sacrifice, whose form consists of mantra and who is devoid of material form, by uttering the above names is certainly endowed with complete vision. (SB1.5.37-38)

This mantra is not exclusively for Krishna and his expansion confirmed by sage Karabhajana
Who describes the form of bhagavan manifest in dvapara in 11.5.29

"I offer obeisance unto Vasudeva, Sańkarşaņa, Pradyumna, and Aniruddha. I offer obeisance unto You, O Bhagavan" (SB 11.5.29).





Mula caturvyūha of Sri krsna