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 ## General references
 
-* Frank Sottile. [*Real solutions to equations from geometry*](https://franksottile.github.io/tmp/sottile.pdf). (See https://franksottile.github.io/teaching/10.S/RSEG.html)
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+* Frank Sottile. [*Real solutions to equations from geometry*](https://franksottile.github.io/tmp/sottile.pdf). (See also https://arxiv.org/abs/math/0609829 and https://franksottile.github.io/teaching/10.S/RSEG.html)
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