diff --git a/doc/src/week37/week37.do.txt b/doc/src/week37/week37.do.txt
index 8f0c30be3..6b659df0a 100644
--- a/doc/src/week37/week37.do.txt
+++ b/doc/src/week37/week37.do.txt
@@ -16,13 +16,20 @@ DATE: today
 !eblock  
 !bblock Material for the lecture on Thursday September 7
   * Statistical interpretation of Ridge and Lasso regression
-  * Resampling techniques, Bootstrap and cross validation
+  * Resampling techniques, Bootstrap and cross validation and bias-variance tradeoff
   * Recommended Reading:
     o Lectures on Resampling methods (these lectures)
     o Bishop 1.3 (cross-validation) and 3.2 (bias-variance tradeoff)
     o Hastie et al Chapter 7, here we recommend 7.1-7.5 and 7.10 (cross-validation) and 7.11 (bootstrap). 
+  * "Video on cross validation":"https://www.youtube.com/watch?v=fSytzGwwBVw"
+  * "Video on bias-variance tradeoff":"https://www.youtube.com/watch?v=EuBBz3bI-aA"
 !eblock
 
+
+!split
+===== Material from last week and relevant for the weekly exercises =====
+
+
 !split 
 ===== Linking the regression analysis with a statistical interpretation =====