College Football Rule Changes for 2021 - The New York Times
2021 NFL rule changes guide - What to expect from more replay help, jersey number flexibility, more - ESPN
How to Watch Every NFL Football Game on a Streaming Service (2023)
2021 N.F.L. Rule Changes: A Viewer's Guide - The New York Times
Latest NFL rule change a reminder that kickoffs are in danger: 'To do nothing was unacceptable'
NFL approves 2 rule changes; postseason OT altered
NFL approves 2 rule changes; postseason OT altered
22 people who will shape the 2022 NFL season
Grading NFL overtime format ideas and proposals - Mandatory possessions, spot and choose, no sudden death, more - ESPN
How NFL rule changes for 2021 will impact the game - Fewer low blocks, expanded review and balanced holding calls - ESPN