With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Wyatt Earp took part in the wagering of something of value and he was American.
text_B: What Bird is That ?. A Guide to the Birds of Australia is a book first published in 1931 by Angus & Robertson in Sydney .. Angus & Robertson. Angus & Robertson. Sydney. Sydney. Authored and illustrated by Neville William Cayley , it was Australia 's first fully illustrated national field guide to birds , a function it served alone for nearly 40 years .. Neville William Cayley. Neville William Cayley. field guide. field guide. In 1960 it was rated the all-time best seller in Australian natural history .. best seller. bestseller. natural history. natural history
not_related.