TY  - RPRT
TI  - A convenient accommodative target for near fixation.
AU  - E F Purcell
PY  - 1967
DO  - 10.1016/0002-9394(67)93676-8
UR  - https://pubmed.ncbi.nlm.nih.gov/6027361/
ID  - 6027361
ER  -