Thanks to the Codeshare Agreement with Air Europa, Aerolíneas Argentinas offers you a second frequency every day to fly to Madrid:

Codeshare Destinations	Flight Operator
Madrid	Air Europa
Non-Stop from/to Buenos Aires or Córdoba
Non-Stop from/to Buenos Aires or Córdoba vía Madrid
Lisboa y Londres vía Madrid

If you are a member of Aerolíneas Argentinas frequent flyer program, when flying any route operated by Air Europa you will be able to earn and redeem miles in your Aerolíneas Plus account.

If you are an Elite Plus member or travelling in Business class you will be able to access Air Europa VIP lounges before boarding an international flight.
Air Europa’s Baggage Policy