diff --git a/init.g b/init.g
index 26638a79f..c81621f51 100644
--- a/init.g
+++ b/init.g
@@ -107,8 +107,6 @@ ReadPackage("semigroups", "gap/attributes/properties.gd");
 ReadPackage("semigroups", "gap/attributes/translat.gd");
 ReadPackage("semigroups", "gap/attributes/rms-translat.gd");
 
-ReadPackage("semigroups", "gap/attributes/dual.gd");
-
 ReadPackage("semigroups", "gap/congruences/congpairs.gd");
 ReadPackage("semigroups", "gap/congruences/congrms.gd");
 ReadPackage("semigroups", "gap/congruences/conguniv.gd");
diff --git a/read.g b/read.g
index 590b0bd6e..d4a127925 100644
--- a/read.g
+++ b/read.g
@@ -80,12 +80,9 @@ ReadPackage("semigroups", "gap/attributes/isorms.gi");
 ReadPackage("semigroups", "gap/attributes/maximal.gi");
 ReadPackage("semigroups", "gap/attributes/normalizer.gi");
 ReadPackage("semigroups", "gap/attributes/properties.gi");
-ReadPackage("semigroups", "gap/attributes/isorms.gi");
 ReadPackage("semigroups", "gap/attributes/translat.gi");
 ReadPackage("semigroups", "gap/attributes/rms-translat.gi");
 
-ReadPackage("semigroups", "gap/attributes/dual.gi");
-
 ReadPackage("semigroups", "gap/congruences/congpairs.gi");
 ReadPackage("semigroups", "gap/congruences/congrms.gi");
 ReadPackage("semigroups", "gap/congruences/conguniv.gi");