diff --git a/bbn_wave_freq_m5atomS3/MonoWedge.h b/bbn_wave_freq_m5atomS3/MonoWedge.h
index 5884040..99152bd 100644
--- a/bbn_wave_freq_m5atomS3/MonoWedge.h
+++ b/bbn_wave_freq_m5atomS3/MonoWedge.h
@@ -51,6 +51,8 @@
     The wedge must be monotonic at all times with respect to Compare,
     EG. by only modifying the structure with wedge_update and pop_front.
 
+    Adopted from; https://github.com/EvanBalster/STL_mono_wedge
+
 */
 
 #include <algorithm>