Some light reading about masks, and links to studies about masks in this document, from a letter written by the Ontario Civil Liberties Association to the WHO:

http://ocla.ca/wp-content/uploads/2020/06/2020-06-21-Letter-OCLA-to-WHO-DG.pdf

(Linked studies have some text that summarizes the main result)

QUOTES from the letter:

"We believe that the WHO recommendation is harmful to public health, and harmful to the very fabric of society. The recommendation is used by governments as a ready-made justification to impose mask use in the general population. The resulting legislative dictates and policies of coercion broadly violate civil, political and human rights. We ask that your ill-conceived recommendation be retracted immediately."

"Second, more importantly, you fail to mention that several randomized controlled trials with verified outcomes (infections) were specifically designed to detect a benefit, and did not find any measurable benefit, for any viral respiratory ...