It wasnarrated that Kuraib the freed slave of 'Abdullah bin 'Abbassaid:
"A son of 'Abdullah bin 'Abbas died, and he said to me:'OKuraib! Get up and see if anyone has assembled (to pray) for myson.'I said: 'Yes.' He said: 'Woe to you, how many do yousee? Forty?' Isaid: 'No, rather there are more.' He said:'Take my son out, for Ibear witness that I hear the Messenger ofAllah (ﷺ) say: "No (groupof) forty believers intercede for abeliever, but Allah will accepttheir intercession."
English reference: Vol. 1, Book 6, Hadith 1489
Arabic reference: Book 6, Hadith 1556