From Sahih Muslim (Hadith 2968):
Abd al-Rahman b. Abi al-Sha'tha' reported:I came to Ibrahim al-Nakha'I and Ibrahim Taimi and said: I intend to combine 'Umra and Hajj this year, whereupon Ibrahim al-Nakha'i said: But your father did not make such intention. Ibrahim narrated on the authority of, his father that he passed by Abu Dharr (Allah be pleased with him) at Rabdha, and made a mention of that, whereupon he said: It was a special concession for us and not for you
Reference: Muslim 2968