TY  - RPRT
TI  - Edge extraction by active defocusing.
AU  - Q M Zhu
AU  - Y Y Hung
AU  - S H Tang
AU  - D H Shi
PY  - 1991
DO  - 10.1163/156856891x00029
UR  - https://pubmed.ncbi.nlm.nih.gov/1751426/
ID  - 1751426
ER  -