Sa'id bin al-Musayyab (may Allah have mercy on him) narrates from Sayyiduna Mu'awiyah (may Allah be pleased with him): "That the Messenger of Allah (peace and blessings be upon him) forbade zur, and zur is that a woman joins (other) hair to her hair."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16774
Sa'id bin al-Musayyab (may Allah have mercy on him) narrates from Sayyiduna Mu'awiyah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) forbade zur.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16775
Imam Qatadah (may Allah have mercy on him) narrates from Sa'id bin al-Musayyab (may Allah have mercy on him) that Sayyiduna Mu'awiyah (may Allah be pleased with him) said: "O people! The Messenger of Allah (peace and blessings be upon him) has forbidden you zur (hair extensions)." Then he brought a black piece of cloth and threw it down in front of them, and said: "This is the thing that a woman puts on her head and then wraps her head-covering over it."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16776
Sa'id bin al-Musayyab (may Allah have mercy on him) said: Sayyiduna Mu'awiyah (may Allah be pleased with him) came to Madinah and stood on the pulpit, holding a braid of hair in his hand, and he said: "I did not think that anyone would do this, for the Messenger of Allah (peace and blessings be upon him) called it zur."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16777
Imam Qatadah (may Allah have mercy on him) narrates, through Sa'id bin al-Musayyab (may Allah have mercy on him), from Sayyiduna Mu'awiyah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever Allah intends good for, He grants him understanding of the religion."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16778