TY  - BOOK
TI  - Mask reduce spread of flu and some viruses, study finds
KW  - Masks
KW  - COVID-19 Pandemic
UR  - http://elibrary.doh.gov.ph/cgi-bin/koha/opac-retrieve-file.pl?id=1b882b40af4d792a363b6a5f00f413ef
ER  -