Manusmriti

siva.sh/manusmriti/4/104

एतांस्त्वभ्युदितान् विद्याद् यदा प्रादुष्कृताग्निषु । तदा विद्यादनध्यायमनृतौ चाभ्रदर्शने ॥ १०४ ॥

sanskrit

When one perceives these (phenomena) all together (in the twilight), after the sacred fires have been made to blaze (for the performance of the Agnihotra), then one must know the recitation of the Veda to be forbidden, and also when clouds appear out of season.

english translation

etAMstvabhyuditAn vidyAd yadA prAduSkRtAgniSu | tadA vidyAdanadhyAyamanRtau cAbhradarzane || 104 ||

hk transliteration by Sanscript