diff --git a/DESCRIPTION b/DESCRIPTION
index 528934c..44dbeb6 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -23,6 +23,7 @@ Imports:
   coin,
   MASS,
   ggplot2,
+  S4Vectors,
   stats,
   methods
 Suggests: 
diff --git a/R/utils.R b/R/utils.R
index 1d34f88..6b2cba1 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -28,7 +28,7 @@ relativeAb <- function(se, assay = 1L) {
     res <- expr_data / div
     assaylist <- assays(se)
     newalist <- append(
-        assaylist, value = S4Vectors::SimpleList(rel_abs = res), after = 0L
+        assaylist, values = S4Vectors::SimpleList(rel_abs = res), after = 0L
     )
     assays(se) <- newalist
     se