diff --git a/mkessler-operators.sty b/mkessler-operators.sty
index dea3e5f..24b5a55 100644
--- a/mkessler-operators.sty
+++ b/mkessler-operators.sty
@@ -140,3 +140,4 @@
 \DeclareMathOperator{\cov}{cov}
 \DeclareMathOperator{\cor}{cor}
 \DeclareMathOperator{\ord}{ord}
+\DeclareMathOperator{\tg}{tg}