This is an excellent price that will not last so book soon!
Availability for most of 2018 on Iberia. Sample dates Tuesday October 9 through Tuesday October 23 2018.
Go here and enter your dates. Find the deal you like, then go to the airline page and and book your tickets.
You may find that the airline price is slightly higher than the price quoted by the OTA (online travel agency). If you want to learn more about OTAs, Scott’s Cheap Flights has an excellent FAQ here.