question: Where is the head office of a Portuguese regional airline that is a subsidiary of TAP Portugal and operates scheduled international and domestic services from its bases at Lisbon Airport and Porto Airport on behalf of a Portuguese regional airline brand name for TAP Portugal which operate short- and medium-haul routes ?
answer: Lisbon Portela Airport
context: Title: Porto Airport
  Passage: Francisco Sá Carneiro Airport (IATA: OPO, ICAO: LPPR) or simply Porto Airport is an international airport near Porto (Oporto), Portugal.  It is located 11 km northwest of the Clérigos Tower in the centre of Porto, in the municipalities of Maia, Matosinhos and Vila do Conde and is run by ANA – Aeroportos de Portugal.  The airport is currently the second-busiest in the country, based on aircraft operations; and the second-busiest in passengers, based on Aeroportos de Portugal traffic statistics, after Lisbon Airport and before Faro Airport.  The airport is a base for easyJet, Ryanair, TAP Portugal and its subsidiary TAP Express.
  Title: Portugália Airlines
  Passage: Portugália Airlines is a Portuguese regional airline with its head office on the grounds of Lisbon Portela Airport in Lisbon.  It is a subsidiary of TAP Portugal and operates scheduled international and domestic services from its bases at Lisbon Airport and Porto Airport on behalf of TAP Express.
  Title: TAP Express
  Passage: TAP Express (Transportes Aéreos Portugueses or TAP for short) is a Portuguese regional airline brand name for TAP Portugal which operate short- and medium-haul routes.  TAP Portugal's lone wholly owned regional airline, Portugália Airlines, operates under the TAP Express banner.  White Airways, an airline owned by Omni Aviation, also operates regular flights for TAP Express using 9 ATR 72 turboprops.  Its head office is on the grounds of Lisbon Portela Airport in Lisbon.
  Title: Groundforce Portugal
  Passage: Groundforce Portugal is a subsidiary company of TAP Portugal, offering aircraft ground handling services in Portugal.  It was created with the privatization of the ground handling services of airline TAP Portugal in October 2005.
citations: Portugália Airlines TAP Express