diff --git a/JavaExamples b/JavaExamples
new file mode 100644
index 0000000..c0259e3
--- /dev/null
+++ b/JavaExamples
@@ -0,0 +1,78 @@
+/// Java Examples
+
+// Mutating immut set, `s` is immut
+void foo(Set<String> s) {
+  Set<String> new_s = s;
+  new_s.add("x"); // ERROR
+}
+
+// Mutating immut set, `new_s` is immut
+void foo(@Mutable Set<String> s) {
+  Set<String> new_s = new HashSet<>(s);
+  new_s.add("x"); // ERROR
+}
+
+// Mutating mut set
+void foo(Set<String> s) {
+  @Mutable Set<String> new_s = new HashSet<>(s);
+  new_s.add("x"); // OK
+}
+
+// Type parameter mutability
+void foo(Set<List<String>> s, List<String> l) {
+  assert s.get(l) != null;
+  List<String> v = s.get(l);
+  l.add("x"); // ERROR
+  v.add("x"); // ERROR
+}
+
+// Immut class and its members
+class Person {
+  String name;
+  List<String> family;
+
+  Person(String n, List<String> f) {
+    this.name = n; // OK
+    this.family = f; // OK
+  }
+
+  void setName(String n) {
+    this.name = n; // ERROR
+  }
+
+  @Mutable List<String> getFamily() {
+    return family; // ERROR
+  }
+}
+
+void foo(Person p) {
+  p.name = "Jenny"; // ERROR
+  p.family.add("Jenny"); // ERROR
+  p.family.getFamily().add("Jenny"); // OK
+}
+
+// Mut class and its members
+@Mutable class Person {
+  String name;
+  List<String> family;
+
+  Person(String n, List<String> f) {
+    this.name = n; // OK
+    this.family = f; // OK
+  }
+
+  void setName(String n) {
+    this.name = n; // OK
+  }
+
+  List<String> getFamily() {
+    return family; // OK
+  }
+}
+
+void foo(Person p) {
+  p.name = "Jenny"; // OK
+  p.family.add("Jenny"); // OK
+  p.family.getFamily().add("Jenny"); // ERROR
+}
+
diff --git a/README.md b/README.md
index ebe78de..27daf42 100644
--- a/README.md
+++ b/README.md
@@ -3,3 +3,8 @@
 
 
 PICO is a type system that supports class level and object level immutability based on Checker Framework.
+
+### Reference
+[Haifeng Shi: Context-Sensitive Optional Type Systems Meet Generics: A Uniform Treatment and Formalization](https://uwspace.uwaterloo.ca/handle/10012/20163)\
+[Lian Sun: An Immutability Type System for Classes and Objects: Improvements, Experiments, and Comparisons](https://uwspace.uwaterloo.ca/handle/10012/16882)\
+[Mier Ta: Context Sensitive Typechecking And Inference: Ownership And Immutability](https://uwspace.uwaterloo.ca/handle/10012/13185)