Sahih Muslim 2882 b
This hadith has been narrated on the authority of 'Abdullah b. Rufai, with the same chain of transmitters (but with the addition of these words):
" When I met Abu Ja'far I told him that she (simply) meant the plain ground. Thereupon Abu Ja'far said: No, by God, she meant the plain ground of Medina.
حَدَّثَنَاهُ أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ رُفَيْعٍ، بِهَذَا الإِسْنَادِ
 وَفِي حَدِيثِهِ قَالَ فَلَقِيتُ أَبَا جَعْفَرٍ فَقُلْتُ إِنَّهَا إِنَّمَا قَالَتْ بِبَيْدَاءَ مِنَ الأَرْضِ فَقَالَ أَبُو جَعْفَرٍ
 كَلاَّ وَاللَّهِ إِنَّهَا لَبَيْدَاءُ الْمَدِينَةِ ‏.‏