TY  - RPRT
TI  - Impossible objects: a special type of visual illusion.
AU  - L S PENROSE
AU  - R PENROSE
PY  - 1958
DO  - 10.1111/j.2044-8295.1958.tb00634.x
UR  - https://pubmed.ncbi.nlm.nih.gov/13536303/
ID  - 13536303
ER  -