Abdullah bin Sahl and Muhayyisah bin Mas'ud (may Allah be pleased with them both) went to Khaybar for some purpose, and they became separated in a grove of date palms. Abdullah bin Sahl (may Allah be pleased with him) was killed. His brother Abd al-Rahman bin Sahl and his cousins Muhayyisah and Huwayyisah (may Allah be pleased with them) came to the Messenger of Allah (peace and blessings be upon him). They described the matter concerning the two. Abd al-Rahman (may Allah be pleased with him) began to speak, and he was the closest relative. The Messenger of Allah (peace and blessings be upon him) said: "The elder has the greater right." Yahya (may Allah have mercy on him) said: Let the speaking begin with the elder. So the two of them spoke.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوكالة / 11436
It is narrated from Abdullah bin Ja'far (may Allah be pleased with them both) that Ali bin Abi Talib (may Allah be pleased with him) disliked disputes. Whenever a matter arose, he would appoint Aqil bin Abi Talib (may Allah be pleased with him) as his agent, and when he grew old, he appointed me as his agent.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوكالة / 11437
Muhammad bin Ishaq (may Allah have mercy on him) narrates from a man of Madinah named Jahm, who narrates from Sayyiduna Ali (may Allah be pleased with him) that he appointed Abdullah bin Ja'far (may Allah be pleased with them both) as his agent in a dispute and said: In disputes there is ruin. Abu al-Zayyad said: "Qahm" refers to places of ruin.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوكالة / 11438