What is the ruling regarding the distribution of the *Nafal* (booty bonus) for a vanguard or returning contingent in military expeditions?

Primary text

When the Imam or his deputy enters hostile territory for warfare, the vanguard contingent (*sariyya*) sent ahead receives one-fourth (*Raba'*) of the spoils after the one-fifth (*khums*) share is set aside. After the one-fifth is taken from what the contingent brings back, the contingent receives one-fourth of the remainder, which is equivalent to another one-fifth. The rest is then divided among the main army and the contingent. Upon the return journey (*ruj'a*), the contingent sent out receives one-third (*Thuluth*) of the spoils after the one-fifth is set aside. After the one-fifth is taken, the contingent receives one-third of what remains, and the rest is divided among the army and the contingent. This view is held by Habib ibn Maslamah, Al-Hasan, Al-Awza'i, and a group. This is supported by the narrations from Habib ibn Maslamah and 'Ubadah ibn al-Samit stating that the Prophet, peace be upon him, gave one-fourth upon initiation and one-third upon return.