C – complex	U – perturbed by close line, but unresolved	R2 – widely reversed
L – shaded to longer wavelengths	D – double	R3 – moderately reversed
S – shaded to shorter wavelengths	B – blend	R4 – slightly reversed
W – wide	H – hazy	R5 – barely detectably reversed
P – perturbed by close line, but resolved	R1 – very widely reversed	* – classification in doubt