With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Howard Hughes expanded an airline.
text_B: The 1977 Copa Libertadores was the 18th edition of CONMEBOL 's top club tournament .. Copa Libertadores. Copa Libertadores. The tournament was won by Boca Juniors after defeating defending champions Cruzeiro for their first Copa Libertadores title .. Boca Juniors. Club Atletico Boca Juniors. Cruzeiro. Cruzeiro Esporte Clube. Copa Libertadores. Copa Libertadores
not_related.