1 files changed, 1 insertions, 1 deletions
diff --git a/Sum.thy b/Sum.thy
index 8f40b74..7e688a2 100644
--- a/Sum.thy
+++ b/Sum.thy
@@ -51,7 +51,7 @@ and
     \<rbrakk> \<Longrightarrow> indSum[A,B] C f (a,b) \<equiv> f a b"
 
 lemmas Sum_rules [intro] = Sum_form Sum_intro Sum_elim Sum_comp
-lemmas Sum_form_conds [elim] = Sum_form_cond1 Sum_form_cond2
+lemmas Sum_form_conds [elim, wellform] = Sum_form_cond1 Sum_form_cond2
 
 \<comment> \<open>Nondependent pair\<close>
 abbreviation Pair :: "[Term, Term] \<Rightarrow> Term"  (infixr "\<times>" 50)