TY  - JOUR
T1  - Measurement of Colour Produced by Contrast
JF  - Proceedings of the Royal Society of London (1854-1905)
VL  - 56
SP  - 221
EP  - 228
PY  - 1894/01/01/
UR  - http://dx.doi.org/10.1098/rspl.1894.0101
M3  - doi:10.1098/rspl.1894.0101
AU  - Abney, W.
ER  -