Breaking down details of NFL's onside kick alternative proposal - Pride Of Detroit
2021 NFL rule changes: Expanded jersey numbers among 6 new rules
NFL fair-catch kick attempts – Quirky Research
Roger Goodell: Eliminating kickoffs remains possible if NFL can't make them safer – Hartford Courant
Denver Broncos prepared for new NFL kickoff rules
NFL owners approve rule changes, including no preseason overtime and expanded jersey number options, NFL News
Among NFL rule change proposals is a fourth-and-15 play replacing an onside kick
NFL clarifies rules proposal on alternate for onside kicks - Los Angeles Times
NFL onside kick rules: Explaining the kickoff changes & why recovery percentage has tanked