TY - JOUR T1 - On Negative After-Images with Pure Spectral Colours JF - Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character (1905-1934) VL - 86 IS - 585 SP - 117 EP - 118 PY - 1913/02/07/ UR - http://dx.doi.org/10.1098/rspb.1913.0006 M3 - doi:10.1098/rspb.1913.0006 AU - Burch, G. ER -