diff --git a/lib/util.js b/lib/util.js
index 1088caa..867978d 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -47,7 +47,7 @@ function sortObjectKeys(obj) {
  */
 function assignWithValid(...sources) {
 	sources.push(assignPredict)
-	return _.assignWith(_, ...sources)
+	return _.assignWith(...sources)
 }
 
 /**
@@ -63,7 +63,7 @@ function assignPredict(older, newer) {
 
 function mergeWithValid(...sources) {
 	sources.push(mergeCustomizer)
-	return _.assignWith(_, ...sources)
+	return _.assignWith(...sources)
 }
 
 function mergeCustomizer(older, newer) {