BṚHADĀRAṆYAKA UPANISHAD · 2.4.10

स यथार्द्रैधाग्नेर् अभ्याहितात् पृथग् धूमा विनिश्चरन्त्य् एव वा अरे ऽस्य महतो भूतस्य निःश्वसितम् एतद् यद् ऋग्वेदो यजुर्वेदः सामवेदो ऽथर्वाङ्गिरस इतिहासः पुराणं विद्या उपनिषदः श्लोकाः सूत्राण्य् अनुव्याख्यानानि व्याख्याननि ।
अस्यैवैतानि निश्वसितानि ॥

sa yathārdraidhāgner abhyāhitāt pṛthag dhūmā viniścaranty eva vā are ’sya mahato bhūtasya niḥśvasitam etad yad ṛgvedo yajurvedaḥ sāmavedo ’tharvāṅgirasa itihāsaḥ purāṇaṃ vidyā upaniṣadaḥ ślokāḥ sūtrāṇy anuvyākhyānāni vyākhyānani ।
asyaivaitāni niśvasitāni ॥

'As clouds of smoke proceed by themselves out of a lighted fire kindled with damp fuel, thus, verily, O Maitreyî, has been breathed forth from this great Being what we have as Rig-veda, Yagur-veda, Sama-veda, Atharvâṅgirasas, Itihâsa (legends), Purâna (cosmogonies), Vidyâ (knowledge), the Upanishads, Slokas (verses), Sûtras (prose rules), Anuvyâkhyânas (glosses), Vyâkhyânas (commentaries). From him alone all these were breathed forth.

F. Max Müller · The Upanishads, Sacred Books of the East 15 (1884)