SB 12.11.22
sa visvas taijasah prajñas
turiya iti vrttibhih
arthendriyasaya-jñanair
bhagavan paribhavyate
Translation:
One can conceive of the Supreme Personality of Godhead in terms of awakened consciousness, sleep and deep sleep — which function respectively through external objects, the mind and material intelligence — and also in terms of the fourth, transcendental level of consciousness, which is characterized by pure knowledge.