diff --git a/PyTeX/format/pytex_formatter.py b/PyTeX/format/pytex_formatter.py
index 878de82..c19d36a 100644
--- a/PyTeX/format/pytex_formatter.py
+++ b/PyTeX/format/pytex_formatter.py
@@ -186,11 +186,14 @@ class PyTeXFormatter(FormatterIF, ABC):
             if self.config.tex_flavour == TeXFlavour.LaTeX2e:
                 return self.shortauthor + '@' + self.raw_name
             elif self.config.tex_flavour == TeXFlavour.LaTeX3:
-                return self.shortauthor + '_' + self.raw_name
+                return self.shortauthor + '_' + self.raw_name.replace('-', '_')
             else:
                 raise NotImplementedError
         else:
-            return self.raw_name
+            if self.config.tex_flavour == TeXFlavour.LaTeX3:
+                return self.raw_name.replace('-', '_')
+            else:
+                return self.raw_name
 
     @property
     def name(self):