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 # Put / Call Ratio Highs and Lows
 
+The idea for these strategies comes from chapter 9 of [*How Markets Really Work*](https://moshferatu.dev/moshferatu/how-markets-really-work) (2012) by Larry Connors.
+
+As with most of the strategies from this book, they are meant to illustrate certain characteristics of the market rather than be traded directly.
+
+The strategies are based on the [Put / Call Ratio indicator](https://moshferatu.dev/moshferatu/ninjatrader/src/branch/main/indicators/put-call-ratio) which calculates the total put options volume divided by the total call options volume.
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