diff --git a/tools/check-source.sh b/tools/check-source.sh
index 415f6221d3..3af7f80691 100755
--- a/tools/check-source.sh
+++ b/tools/check-source.sh
@@ -189,6 +189,13 @@ for f in $texfiles; do
 done |
     fail '"shall", "should", or "may" inside a note' || failed=1
 
+# Comma after e.g. and i.e.
+grep -n "e\.g\.[^,]" $texfiles |
+    fail '"e.g." must be followed by a comma'
+grep -n "i\.e\.[^,]" $texfiles |
+    fail '"i.e." must be followed by a comma'
+
+
 # \logop should use lowercase arguments
 grep -n '\\logop{[^}]*[^andor}][^}]*}' $texfiles |
     fail 'bad argument for \\logop' || failed=1