كتاب الحج
15  
The Book of Pilgrimage
(97)
Chapter: The virtue of the Masjid of Quba', and the virtue of praying therein and visiting it
(97)
باب فَضْلِ مَسْجِدِ قُبَاءٍ وَفَضْلِ الصَّلاَةِ فِيهِ وَزِيَارَتِهِ ‏‏
Sahih Muslim 1399 i

This hadlth has been narrated on the authority of Ibn Dinar, but he made no mention of:

" Every Saturday."
وَحَدَّثَنِيهِ عَبْدُ اللَّهِ بْنُ هَاشِمٍ، حَدَّثَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنِ ابْنِ دِينَارٍ، بِهَذَا الإِسْنَادِ ‏.‏ وَلَمْ يَذْكُرْ كُلَّ سَبْتٍ ‏.‏
Reference : Sahih Muslim 1399i
In-book reference : Book 15, Hadith 601
USC-MSA web (English) reference : Book 7, Hadith 3230
  (deprecated numbering scheme)