وَهُوَ الْبَيَاضُ الَّذِي يُرَى فِي الْأُفُقِ بَعْدَ الْحُمْرَةِ عِنْدَ أَبِي حَنِيفَةَ، وَقَالَ أَبُو يُوسُفَ وَمُحَمَّدٌ: هُوَ الْحُمْرَةُ
Translation: For Abu Hanifah, shafaq is the whiteness visible on the horizon after the red glow; Abu Yusuf and Muhammad said it is the redness.
Abu Hanifah ends Maghrib when the later whiteness disappears. The two disciples end Maghrib when the red glow disappears. As a result, they also differ about the start of Isha.