diff --git a/slides.md b/slides.md
index fdfcbb8..bd48389 100644
--- a/slides.md
+++ b/slides.md
@@ -380,9 +380,7 @@
 
 ```java
 sealed interface List<T> {
-
     record NonEmpty<T>(T head, List<T> tail) implements List<T> {}
-
     record Empty<T>() implements List<T> {}
 }
 ```
@@ -450,9 +448,7 @@
 
 ```java
 sealed interface Tree<T> {
-
     record Node<T>(T value, Tree<T> left, Tree<T> right) implements Tree<T> { }
-
     record Leaf<T>(T value) implements Tree<T> {}
 }
 ```
@@ -463,9 +459,7 @@
 
 ```java
 sealed interface Optional<T> {
-
     record Empty<T>() implements Optional<T> { }
-
     record Present<T>(T value) implements Optional<T> {}
 }
 ```
@@ -476,7 +470,6 @@
 
 ```java
 sealed interface Optional<T> {
-
     default <R> Optional<R> map(Function<T, R> mapper) {
         return switch (this) {
             case Present<T>(var value) -> new Present<>(mapper.apply(value));
@@ -492,7 +485,6 @@
 
 ```java
 sealed interface Optional<T> {
-
     default Optional<T> filter(Predicate<T> filter) {
         return switch (this) {
             case Present<T>(var value) when filter.test(value) -> this;
@@ -509,7 +501,6 @@
 
 ```java
 sealed interface Optional<T> {
-
     default <R> R fold(Supplier<R> onEmpty, Function<T, R> onPresent) {
         return switch (this) {
             case Present<T>(var value) -> onPresent.apply(value);
@@ -525,9 +516,7 @@
 
 ```java
 sealed interface Either<L, R> {
-
     record Left<L, R>(L left) implements Either<L, R> { }
-
     record Right<L, R>(R right) implements Either<L, R> {}
 }
 ```
@@ -604,11 +593,9 @@
 # ADTs: DSLs
 
 ```java
-sealed interface Expr {
-    static void main() {
-        sum(val(1), val(2)).print();
-        times(diff(val(10), val(8)), val(2)).print();
-    }
+static void main() {
+    sum(val(1), val(2)).print();
+    times(diff(val(10), val(8)), val(2)).print();
 }
 ```
 
@@ -953,6 +940,8 @@
 # Links
 
 - [Data Oriented Programmig](https://www.infoq.com/articles/data-oriented-programming-java/) Brian Goetz
+- [Why ADTs are important?](https://www.youtube.com/watch?v=LkqTLJK2API)
+- [Java 23: Restoring the Balance with Primitive Patterns](https://nipafx.dev/inside-java-newscast-66/)
 
 <!-- TODO: