added level 3 plotting visual tutorial

Author: adevroy569

episodes/introduction.md

@@ -183,4 +183,4 @@ In the next episodes we will:
 |-------------------|------------------------------------------------------------------------------------------------------------|
 | <a href="https://colab.research.google.com/github/SpatialTurn/DataCollection-Notebooks/blob/main/Census/goodbadplotting.ipynb" target="_blank">Beginner</a>  | Basics of Good & Bad Plotting |
 | <a href="https://colab.research.google.com/github/SpatialTurn/DataCollection-Notebooks/blob/main/Census/complexvisuals.ipynb" target="_blank">Intermediate</a>  | Basics of More Complex Visuals |
-| <a href="https://colab.research.google.com/github/SpatialTurn/DataCollection-Notebooks/blob/main/Census/.ipynb" target="_blank">Complex</a>  | Basics of 3D Visuals |
+| <a href="https://colab.research.google.com/github/SpatialTurn/DataCollection-Notebooks/blob/main/Census/hardestvisuals.ipynb" target="_blank">Complex</a>  | Basics of 3D Visuals |