TY  - RPRT
TI  - Leonardo's constraint: two opaque objects cannot be seen in the same direction.
AU  - Hiroshi Ono
AU  - Linda Lillakas
AU  - Philip M Grove
AU  - Masahiro Suzuki
PY  - 2003
DO  - 10.1037/0096-3445.132.2.253
UR  - https://pubmed.ncbi.nlm.nih.gov/12825639/
ID  - 12825639
ER  -