diff --git a/Doc/ACKS.txt b/Doc/ACKS.txt
index 5f6e12f..32943bd 100644
--- a/Doc/ACKS.txt
+++ b/Doc/ACKS.txt
@@ -73,6 +73,7 @@
    * Travis B. Hartwell
    * Tim Hatch
    * Janko Hauser
+   * Thomas Heller
    * Bernhard Herzog
    * Magnus L. Hetland
    * Konrad Hinsen