صحيح البخاري
Sahih Bukhari
كتاب الجهاد والسير
The Book of Jihad (Fighting For Allah’S Cause)
باب وجوب النفير وما يجب من الجهاد والنية:
Chapter. The obligation of going out for Jilhad when there is a general call to arms, and what sort of Jihad and intentions are compulsory.