With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Wyatt Earp took part in the gunfight at O.K. Corral.
text_B: A Fighting Man of Mars is a science fantasy novel by American writer Edgar Rice Burroughs , the seventh of his Barsoom series .. Edgar Rice Burroughs. Edgar Rice Burroughs. Barsoom. Barsoom. science fantasy. science fantasy. Burroughs began writing it on February 28 , 1929 , and the finished story was first published in Blue Book Magazine as a six-part serial in the issues for April to September , 1930 .. Blue Book. Blue Book ( magazine ). It was later published as a complete novel by Metropolitan in May , 1931 .
not_related.