Reports: Yankees used dugout phone, replay room to steal signs in 2015-16
Mlb Sign-stealing Scandal
Sign stealing - Wikipedia
MLB Letter Confirms Yankees Used Technology for Sign Stealing - The New York Times
Sign of times: MLB gives OK to electronic pitch calling
Derek Jeter's Hall of Fame election was one vote short of unanimous. Thank goodness.
Commissioner's 2017 Letter to the Yankees on Sign Stealing - The New York Times
SNY Exclusive: The 'Yankee Letter' revealed : r/baseball
Mlb Sign-stealing Scandal