diff --git a/gsl.yaml b/gsl.yaml
index e1776cf45bba29b4ddfeb8dc2e460e0b82b36f9b..318f6efaa559d49f771d48696a0778db75a5fb50 100644
--- a/gsl.yaml
+++ b/gsl.yaml
@@ -1,4 +1,4 @@
 version_control: git
 src_repo: https://git.savannah.gnu.org/git/gsl.git
 tag_prefix: release-
-seperator: -
+seperator: "-"