fix the reference in the docs
@@ -103,7 +103,7 @@ public final class MathExpressions {
* exponential moving average calculation, with the most recent documents contributing the most weight.
* @return the new expression
* @mongodb.server.release 5.0
- * @aggregation.expression expMovingAvg
+ * @aggregation.expression $expMovingAvg
* @see dev.morphia.aggregation.experimental.Aggregation#setWindowFields(SetWindowFields)
* @since 2.3
*/
