White House COVID-19 Response Team media briefings, May 13, 2021, May 18, 2021.

Chicago Tribune: “Following CDC guidelines, Gov. J.B. Pritzker says those who are fully vaccinated can drop masks in most situations, but Chicago maintaining status quo for now.”

COVID19.CA.gov: “California will align its mask guidance with CDC’s on June 15, 2021.”

Colorado Department of Public Health and Environment: “Guidance for wearing masks.”

Michigan.gov: “May 15, 2021 Gatherings and Face Mask Order.”

Connecticut’s Official State Website: “Connecticut COVID-19 Response.”

Delaware.gov: “Governor Carney to Lift Delaware Mask Mandate Effective May 21.”

DCHealth: “Coronavirus Situational Update.”

Kentucky.gov: “Gov. Beshear: Economy Set for Liftoff as Final Capacity Limits End June 11.”

State of Maine: “Face Covering Executive Order FAQs.”

Office of Governor Larry Hogan: “Governor Hogan Announces End of Statewide Mask Mandate.”

NC Governor Roy Cooper: “Following New CDC Guidance on Face Coverings, Governor Cooper Lifts Many COVID-19 Restrictions.”

Minnesota COVID-19 Response: “Safely ending COVID-19 restrictions.”

Nevada Health Response: “Nevada Adopts Updated CDC Mask Guidance.”

Office of the Governor Michelle Lujan Grisham: “Updated public health order in effect; New Mexico adopts CDC mask guidance for fully vaccinated individuals.”

New York State: “Governor Cuomo Announces New York State to Adopt New CDC Guidance on Mask Use and Social Distancing for Fully Vaccinated Individuals.”

Ohio Department of Health: “Governor DeWine Statement on New CDC Mask Guidance.”

Oregon.gov: “Oregon Mask Requirements.”

Pennsylvania Department of Health: “Updated Order of the Secretary of the Pennsylvania Department of Health Requiring Universal Face Coverings.”

Rhode Island Department of Health: “Protect Your Household from COVID-19.”

Office of Governor Phil Scott: “Governor Phil Scott Lifts Mask Mandate For Vaccinated Individuals, Accelerates Vermont Forward Plan.”

Virginia Governor Ralph S. Northam: “Governor Northam Lifts Mask Mandate to Align with CDC Guidance, Announces Virginia to End COVID-19 Mitigation Measures on May 28.”

King County: “Statewide requirement to wear face coverings.”

Office of the Governor Jim Justice: “COVID-19 UPDATE: Gov. Justice lifts face covering requirement for fully vaccinated West Virginians.”