diff --git a/NAMESPACE b/NAMESPACE
index 722b28b..7d42cb5 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -25,6 +25,7 @@
 importFrom(stringr,str_match_all)
 importFrom(stringr,str_replace_all)
 importFrom(stringr,str_split)
+importFrom(stringr,str_sub)
 importFrom(stringr,str_trim)
 importFrom(utils,read.csv)
 importFrom(xml2,"xml_attr<-")