From Sahih Bukhari (Hadith 1863):
Narrated Ibn `Abbas:When the Prophet (ﷺ) returned after performing his Hajj, he asked Um Sinan Al-Ansari, "What did forbid you to perform Hajj?" She replied, "Father of so-and-so (i.e. her husband) had two camels and he performed Hajj on one of them, and the second is used for the irrigation of our land." The Prophet (ﷺ) said (to her), "Perform `Umra in the month of Ramadan, (as it is equivalent to Hajj or Hajj with me (in reward)
Reference: Bukhari 1863