With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Battle Studies World Tour was a tour of the US only.
text_B: Battle Studies World Tour was a worldwide tour by American singer John Mayer .. John Mayer. John Mayer. Battle Studies. Battle Studies ( album ). The tour spanned across the United States , Canada , Denmark , Australia , and the Netherlands , promoting his 2009 album Battle Studies .. Battle Studies. Battle Studies ( album )
related.