Some scribbles on relations and functions.

thesis.bib

@@ -1336,4 +1336,19 @@
   author = {William Shakespeare},
   title  = {The {Tragedy} of {Hamlet}, {Prince} of {Denmark}},
   year   = {1564-1616}
+}
+
+# Introductory PL books
+@book{Pierce02,
+  author    = {Benjamin C. Pierce},
+  title     = {Types and programming languages},
+  publisher = {{MIT} Press},
+  year      = {2002}
+}
+
+@book{Harper16,
+  author    = {Robert Harper},
+  title     = {Practical Foundations for Programming Languages (2nd. Ed.)},
+  publisher = {Cambridge University Press},
+  year      = {2016}
 }