Update "colour.plotting.multi_illuminant_spd_plot" definition plot title.
@@ -499,7 +499,7 @@ def multi_illuminant_spd_plot(illuminants=None, **kwargs):
settings = {
'title':
- '{0} - Illuminants Spectral Power Distribution'.format(
+ '{0} - Illuminants Spectral Power Distributions'.format(
', '.join([spd.strict_name for spd in spds])),
'y_label':
'Relative Power'
