Shiva Purana

siva.sh/siva-purana/uma-samhita/29/24

सृज्यमानाः प्रजाश्चैव नावर्द्धन्त यदा तदा ।। द्विधा कृत्वात्मनो देहं स्त्री चैव पुरुषोऽभवत्।। २४ ।।

sanskrit

When the beings created did not increase he dichotomised his body and became man and woman.

english translation

sRjyamAnAH prajAzcaiva nAvarddhanta yadA tadA || dvidhA kRtvAtmano dehaM strI caiva puruSo'bhavat|| 24 ||

hk transliteration by Sanscript