Hadith 506920
Chapter 18: Fasting - كتاب الصيام
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ عَمِّهِ أَبِي سُهَيْلِ بْنِ مَالِكٍ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّهُ قَالَ إِذَا دَخَلَ رَمَضَانُ فُتِّحَتْ أَبْوَابُ الْجَنَّةِ وَغُلِّقَتْ أَبْوَابُ النَّارِ وَصُفِّدَتِ الشَّيَاطِينُ .
Yahya related to me from Malik from his paternal uncle Abu Suhayl ibn Malik from his father that Abu Hurayra said, "When Ramadan comes the gates of the Garden are opened and the gates of the Fire are locked, and the shayatin are chained."
Reference Muwatta Malik 506920
USC-MSA web (English) reference : Book 18, Hadith 59