TY  - RPRT
TI  - Visual impairment: facing possible blindness.
AU  - C J Heppen
AU  - S B Petersen
PY  - 1979
DO  - 10.1300/j010v05n01_05
UR  - https://pubmed.ncbi.nlm.nih.gov/515889/
ID  - 515889
ER  -