Musnad Abu Ya'la al-Mawsili 2:59

Abu Khaythama and al-Qawariri narrated to us, they said: Sufyan ibn 'Uyaynah narrated to us, from 'Asim ibn 'Ubayd Allah ibn 'Asim, from 'Abd Allah ibn 'Amir ibn Rabi'ah, from his father, from 'Umar ibn al-Khattab, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Perform Hajj and 'Umrah in succession, for the succession between them negates poverty and sins, just as the bellows negates the dross of iron."