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 | ![SuperNOVAS coordinate systems and conversions](resources/SuperNOVAS-systems.png) |
 |:--:| 
-| __Figure 1.__ *SuperNOVAS Coordinate Systems and Conversions*. Functions indicated in bold face are available in NOVAS C also. All other functions are available in SuperNOVAS only.              |
+| __Figure 1.__ *SuperNOVAS Coordinate Systems and Conversions*. Functions indicated in bold face are available in NOVAS C also. All other functions are available in SuperNOVAS only. Dotted arrows indicate possible loss of precision due to the inadequacy of the old precession-nutation model |
 
 
 <a name="sidereal-example"></a>
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