With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Howard Stern has sold over one million copies of his movies.
text_B: This article details the 2011 -- 12 UEFA Europa League first qualifying round .. All times are CEST -LRB- UTC +02 :00 -RRB- .. CEST. Central European Summer Time
not_related.