Sahih Muslim
The Book of Virtue, Good Manners and Joining of the Ties of Relationship (Kitab Al-Birr was-Salat-I-wal-Adab)
Book Number: 032 / Hadith Number: 6283
Umm Darda' reported on the authority of Abu Darda' as saying: I heard Allah's Messenger (may peace be upon him) as saying: The invoker of curse would neither be witness nor intercessor on the Day of Resurrection.