Evidence Shows Masks Really Do Reduce the Spread of COVID-19 and Lower Infection Risk

Trends in County-Level COVID-19 Incidence in Counties With and Without a Mask Mandate — Kansas, June 1–August 23, 2020

Infographic: What We Know About How Masks Can Slow Disease Spread

Lifting Universal Masking in Schools — Covid-19 Incidence among Students and Staff

N95, KN95 masks provide best protection against covid, CDC study shows - The Washington Post

You asked, we're answering: Your top questions about Covid-19 and vaccines

Masks save lives: Here's what you need to know - Harvard Health

CDC encourages people to wear masks to prevent spread of Covid, flu, RSV

Effectiveness of Face Masks in Preventing Airborne Transmission of SARS-CoV-2

Community Use Of Face Masks And COVID-19: Evidence From A Natural Experiment Of State Mandates In The US

Respiratory virus shedding in exhaled breath and efficacy of face masks

An evidence review of face masks against COVID-19

Mythbusters

Mask wearing in community settings reduces SARS-CoV-2 transmission

Mythbusters

COVID-19: Does mask wearing decrease transmission? CCDR 47(2)