TY  - JOUR
T1  - Colour Photometry. Part III. 
JF  - Proceedings of the Royal Society of London (1854-1905)
VL  - 50
SP  - 369
EP  - 372
PY  - 1891/01/01/
UR  - http://dx.doi.org/10.1098/rspl.1891.0048
M3  - doi:10.1098/rspl.1891.0048
AU  - De.W.Abney, W.
AU  - Festing, M.
ER  -