Roger Federer Secures No. 1 Ranking at Age 36 - The New York Times
Gauff becomes ITF Juniors world No. 1
World no. 1 junior Chun Hsin Tseng eyes Grand Slams history - Official Site of the 2023 US Open Tennis Championships - A USTA Event
Roger Federer, Floundering in Heat and Humidity, Shows He's Only Human - The New York Times
Norrie: Goal is World No. 1
At 36, Roger Federer Becomes Oldest No. 1 In Tennis
Swiatek, Gauff lose at Australian Open; Korda in 1st Slam QF
Australian Open 2018: Djokovic, Federer win; Muguruza out - Sports Illustrated
2018 Novak Djokovic tennis season - Wikipedia
Explainer: How tennis rankings actually get it right
Roger Federer retiring from pro tennis at age 41: 'The tires finally wore out' - oregonlive.com
Hounds Make History with First Ever #1 Ranking - UIndy Athletics
Paula Badosa picks between Grand Slam title and No. 1 ranking
ATP Rankings Movers: Roger Federer Returns To No. 1 | ATP Tour | Tennis
Australian Open 2018: Rafael Nadal wins, Americans lose - Sports Illustrated
2018 champion Kerber vs. No. 1 Barty in Wimbledon semifinals – Oneida Dispatch
Francesca Di Lorenzo vs. Christina McHale Full Match | 2018 US Open Round 1 - YouTube
U.S. Open 2018: No. 1-seed Simona Halep upset in 1st round by No. 44 Kaia Kanepi – The Denver Post
2018 Australian Open: No. 1 Halep wins classic, will face Wozniacki in final - CBSSports.com
Winning the tournament and being No. 1 again' – Carlos Alcaraz reveals goal ahead of Indian Wells | Tennis Buzz | capjournal.com
List of ATP number 1 ranked singles tennis players - Wikipedia
Wozniacki overtakes Halep to return to WTA World No.1
