TY  - BOOK
AU  - Held,Richard
TI  - Image, object, and illusion: readings from Scientific American 
SN  - 0716705052
U1  - 612.84 
PY  - 1974///
CY  - San Francisco
PB  - W. H. Freeman
KW  - Optical illusions
KW  - Psychology
N1  - Bibliography: p. [132]-134
ER  -