diff --git a/docs/2_Theoretical_background/Ne-500.md b/docs/2_Theoretical_background/Ne-500.md
index ab3fa6c..08c70b7 100644
--- a/docs/2_Theoretical_background/Ne-500.md
+++ b/docs/2_Theoretical_background/Ne-500.md
@@ -38,5 +38,5 @@ The values for the Ne 500 indicator range between 0 and 1, with 0 indicating all
 
 See section [How to estimate Ne?](https://aliciamstt.github.io/guidelines-genetic-diversity-indicators/docs/3_Howto_guides_examples/Populations_sizes.html#how-to-estimate-population-sizes) for more details on how to obtain Ne data from genetic or Nc information.
 
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+[Previous: Genetic diveristy and indicators](https://aliciamstt.github.io/guidelines-genetic-diversity-indicators/docs/2_Theoretical_background/Genetic_div_indicators.html#genetic-diversity-and-indicators){: .btn .btn-blue .mr-4 }
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