diff --git a/selected/compilers.md b/selected/compilers.md
index dca87dc..40996bd 100644
--- a/selected/compilers.md
+++ b/selected/compilers.md
@@ -40,22 +40,19 @@ ok what do we want to cover
 
 - semantic analysis / type checking
 
-| Title                         | Page |
-|-------------------------------|------|
-| Semantic Analysis, Explained  | https://monkeylearn.com/blog/semantic-analysis/ |
-| Wikipedia                     | https://en.wikipedia.org/wiki/Compiler#Front_end |
-| SA in Compiler Design         | https://www.geeksforgeeks.org/semantic-analysis-in-compiler-design/ |
-| Compiler Design - SA          | https://www.tutorialspoint.com/compiler_design/compiler_design_semantic_analysis.htm |
-| What is Semantic Analysis?    | https://home.adelphi.edu/~siegfried/cs372/372l8.pdf |
-| SA in Compiler Design         | https://iq.opengenus.org/semantic-analysis-in-compiler-design/ |
-| Implementation of SA          | https://pgrandinetti.github.io/compilers/page/implementation-semantic-analysis/ |
-| What is SA in a Compiler?     | https://pgrandinetti.github.io/compilers/page/what-is-semantic-analysis-in-compilers/ |
-| SA - An Overview              | https://www.sciencedirect.com/topics/computer-science/semantic-analysis |
-| SA (Slides)                   | https://www.computing.dcu.ie/~davids/courses/CA4003/CA4003_Semantic_Analysis_2p.pdf |
-| V: The Semantic Analysis!     | https://www.youtube.com/watch?v=j172YWmBk5A |
-| V: Intro to Semantic Analysis | https://www.youtube.com/watch?v=cC8YRnDGMwI |
-| V: Compiler Design SA         | https://www.youtube.com/watch?v=57U6pQRnSJA |
-| V: Semantic Analysis: Intro   | https://www.youtube.com/watch?v=7pHmBEkeIdQ |
+|Star| Title                         | Page |
+|    |-------------------------------|------|
+|    | Wikipedia                     | https://en.wikipedia.org/wiki/Compiler#Front_end |
+|    | Compiler Design - SA          | https://www.tutorialspoint.com/compiler_design/compiler_design_semantic_analysis.htm |
+|*   | What is Semantic Analysis?    | https://home.adelphi.edu/~siegfried/cs372/372l8.pdf |
+|*?  | SA in Compiler Design         | https://iq.opengenus.org/semantic-analysis-in-compiler-design/ |
+|*?  | Implementation of SA          | https://pgrandinetti.github.io/compilers/page/implementation-semantic-analysis/ |
+|*?  | What is SA in a Compiler?     | https://pgrandinetti.github.io/compilers/page/what-is-semantic-analysis-in-compilers/ |
+|    | SA (Slides)                   | https://www.computing.dcu.ie/~davids/courses/CA4003/CA4003_Semantic_Analysis_2p.pdf |
+|    | V: The Semantic Analysis!     | https://www.youtube.com/watch?v=j172YWmBk5A |
+|    | V: Intro to Semantic Analysis | https://www.youtube.com/watch?v=cC8YRnDGMwI |
+|    | V: Compiler Design SA         | https://www.youtube.com/watch?v=57U6pQRnSJA |
+|    | V: Semantic Analysis: Intro   | https://www.youtube.com/watch?v=7pHmBEkeIdQ |
 
 | Title                            | Page |
 |----------------------------------|------|