NFL rule changes: Modified instant replay, more positions allowed to wear single-digit jerseys - The Washington Post
2018 NFL offseason rule changes primer - Guide for helmet, kickoff, catch tweaks to remember - ESPN
NFL considers a change to the catch rule
Replay review in gridiron football - Wikipedia
NFL adds approved ruling on fumble/safety reviews to casebook for playoffs – Football Zebras
NFL to tweak concussion protocol after frightening injuries
How the NFL's Proposed Rule Changes Could Affect the League - The Ringer
NFL to tweak replay reviews
First Call: Chase Claypool, Damar Hamlin starting to pop in camps; replay rule change; Guardian Caps in games?
In defense of the targeting rule, and the NCAA's proposed changes to it - The Athletic
NFL replay reviews, challenges drop with new rules and tech - ESPN
Owners authorize Competition Committee to tweak replay review for pass interference - NBC Sports
On Further Review, the NFL's Instant Replay is Finally Instant
Has NFL found answer to fewer challenges with 'replay assistance'?