X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fnlibrary%2Ftopology%2Figft.ma;h=21194951bc91831f211012245fae1737f245f311;hb=c2b39b7ef14ab610cb2056fb6b75492c7068288e;hp=d0068dbf7e5f367c05f1b72616f132091b78834a;hpb=2f9e86d966ef765b9eff2483983ff1fe635bb138;p=helm.git

diff --git a/helm/software/matita/nlibrary/topology/igft.ma b/helm/software/matita/nlibrary/topology/igft.ma
index d0068dbf7..21194951b 100644
--- a/helm/software/matita/nlibrary/topology/igft.ma
+++ b/helm/software/matita/nlibrary/topology/igft.ma
@@ -982,6 +982,8 @@ We now proceed with the proof of the infinity rule.
 D*)
 
 
+alias symbol "covers" = "new covers set".
+alias symbol "covers" = "new covers".
 alias symbol "covers" = "new covers set".
 ntheorem new_coverage_infinity:
   ∀A:nAx.∀U:Ω^A.∀a:A. (∃i:𝐈 a. 𝐈𝐦[𝐝 a i] ◃ U) → a ◃ U.