diff --git a/truth-table.lisp b/truth-table.lisp
index 101783f..a4e6b41 100644
--- a/truth-table.lisp
+++ b/truth-table.lisp
@@ -1,3 +1,18 @@
+;; truth-table.lisp -- Generate truth tables from proposition strings
+;; Copyright (C) 2024  Alexander Rosenberg
+;;
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #+slynk (ql:quickload '(:uiop :with-user-abort) :silent t)
 
 (defpackage :truth-table