Sign stealing - Wikipedia
MLB letter to Yankees sheds light on illicit use of technology during 2015 and 2016 seasons
Yankees sign stealing: Judge orders letter from MLB unsealed - Sports Illustrated NY Yankees News, Analysis and More
MLB Letter Unsealed: Yankees Used Technology in 2015 & '16 To Help Baserunners
MLB letter to New York Yankees about sign-stealing allegations to be made public despite appeal - ESPN
New York Yankees, a sealed letter, MLB, and the biggest cheating scandal in the history of the sports: Will the Houston Astros receive justice?
MLB Yankees Letter Sign Stealing Court Orders Release –
Leaked 'Yankee Letter' confirms team stole signs in 2015-16, which MLB hid from public
Yankee letter,' explained: What's revealed in early release of letter by MLB commissioner Rob Manfred