With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Steffi Graf is a professional tennis player.
text_B: The Association of Tennis Professionals -LRB- ATP -RRB- was formed in September 1972 by Donald Dell , Bob Briner , Jack Kramer , and Cliff Drysdale to protect the interests of male professional tennis players .. tennis. tennis. Donald Dell. Donald Dell. Bob Briner. Bob Briner. Jack Kramer. Jack Kramer. Cliff Drysdale. Cliff Drysdale. Drysdale became the first President .. Since 1990 , the association has organized the worldwide tennis tour for men and linked the title of the tour with the organization 's name .. tennis. tennis. In 1990 the organization was called the ATP Tour , which was renamed in 2001 as just ATP and the tour being called ATP Tour .. In 2009 the name was changed again and is now known as the ATP World Tour .. It is an evolution of the tour competitions previously known as Grand Prix tennis tournaments and World Championship Tennis -LRB- WCT -RRB- .. tennis. tennis. Grand Prix tennis tournaments. Grand Prix tennis circuit. World Championship Tennis. World Championship Tennis. The ATP 's global headquarters are in London , United Kingdom .. London. London. ATP Americas is based in Ponte Vedra Beach , United States ; ATP Europe is headquartered in Monaco ; and ATP International , which covers Africa , Asia and Australasia , is based in Sydney , Australia .. Monaco. Monaco. Ponte Vedra Beach. Ponte Vedra Beach, Florida. Sydney. Sydney. The counterpart organization in the women 's professional game is the Women 's Tennis Association -LRB- WTA -RRB- .
related.