Several Cowboys change jersey numbers, some off limits
From No. 1 to 77, the Dallas Mavericks explain the story behind their jersey numbers - The Athletic
Cowboys issue Tony Romo's old number to Jaylon Smith - NBC Sports
Rank'Em: Cowboys' Most Sacred Jersey Numbers
NFL teams should stop retiring jersey numbers - Sports Illustrated
Why it's ridiculous to think Tony Romo will ever leave CBS to play again
Enter player zero: NFL stars excited by jersey number rule change, News
Is 49ers' Brock Purdy real deal? Historic results don't sway critics
Enter player zero: NFL stars excited by jersey number rule change, News
Dallas Cowboys - Wikipedia