With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Heinrich Himmler commanded the Luftwaffe.
text_B: Coari River is a tributary of the Amazon River -LRB- Solimoes section -RRB- in the Amazonas state in north-western Brazil .. Amazonas. Amazonas ( Brazilian state ). tributary. tributary. Amazon River. Amazon River. Solimoes. Solimoes. Brazil. Brazil
not_related.