صحيح البخاري
Sahih Bukhari
كتاب الصوم
The Book of As-Saum (The Fasting).
باب الوصال، ومن قال ليس فى الليل صيام:
Chapter. Al-Wisal [i.e., to observe Saum (fast) continuously without eating or drinking anything by day or night, may be for a day or two or more].
