Srimad-Bhagavatam: Canto 12 - Chapter 1 - Verse 34
Sanskrit:
दिव्याब्दानां सहस्रान्ते चतुर्थे तु पुन: कृतम् ।भविष्यति तदा नृणां मन आत्मप्रकाशकम् ॥ ३४ ॥
ITRANS:
divyābdānāṁ sahasrāntecaturthe tu punaḥ kṛtambhaviṣyati tadā nṝṇāṁmana ātma-prakāśakam
Translation:
After the one thousand celestial years of Kali-yuga, the Satya-yuga will manifest again. At that time the minds of all men will become self-effulgent.