BṚHADĀRAṆYAKA UPANISHAD · 4.5.1

अथ ह याज्ञवल्क्यस्य द्वे भार्ये बभूवतुर् मैत्रेयी च कात्यायनी च ।
तयोर् ह मैत्रेयी ब्रह्मवादिनी बभूव ।
स्त्रीप्रज्ञैव तर्हि कात्यायनी ।
अथ ह याज्ञवल्क्यो ऽन्यद् वृत्तम् उपाकरिष्यन् ॥

atha ha yājñavalkyasya dve bhārye babhūvatur maitreyī ca kātyāyanī ca ।
tayor ha maitreyī brahmavādinī babhūva ।
strīprajñaiva tarhi kātyāyanī ।
atha ha yājñavalkyo ’nyad vṛttam upākariṣyan ॥

Yâgñavalkya had two wives, Maitreyî and Kâtyâyanî. Of these Maitreyî was conversant with Brahman, but Kâtyâyanî possessed such knowledge only as women possess. And Yâgñavalkya, when he wished to get ready for another state of life (when he wished to give up the state of a householder, and retire into the forest),

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