Chapter on Preparing for Ihram
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 3|Chapter 46
وَ فِي رِوَايَةِ جَمِيلٍ أَنَّهُ قَالَ: «غُسْلُ يَوْمِكَ يُجْزِيكَ لِلَيْلَتِكَ وَ غُسْلُ لَيْلَتِكَ يُجْزِيكَ لِيَوْمِكَ ».
In a narration by Jamil, Imam عليه السلام said: "The ghusl of your day suffices for your night, and the ghusl of your night suffices for your day."
- Ṣaḥīḥ al-Faqīh, p. 125