diff --git a/Doc/lib/libcodecs.tex b/Doc/lib/libcodecs.tex
index 3055cdf944a..7d4a4cefb61 100644
--- a/Doc/lib/libcodecs.tex
+++ b/Doc/lib/libcodecs.tex
@@ -616,6 +616,10 @@ exist:
         {865, IBM865}
         {Danish, Norwegian}
 
+\lineiii{cp866}
+        {866, IBM866}
+        {Russian}
+
 \lineiii{cp869}
         {869, CP-GR, IBM869}
         {Greek}