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 ?
Sentence (from "TAP Express"): Its head office is on the grounds of Lisbon Portela Airport in Lisbon.
Relevant evidence: Yes