TY  - RPRT
TI  - The upside down facemask again.
AU  - W C Edmondson
AU  - A Rushton
PY  - 1992
DO  - 10.1111/j.1365-2044.1992.tb02199.x
UR  - https://pubmed.ncbi.nlm.nih.gov/1519707/
ID  - 1519707
ER  -