diff --git a/Project.toml b/Project.toml
index 35508b3..746b3b7 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "FiniteMPS"
 uuid = "6b572690-f317-4dad-a5fe-5fe73a0b7d42"
 authors = ["qyli <liqiaoyi@itp.ac.cn>"]
-version = "1.5.0"
+version = "1.6.0"
 
 [deps]
 AbstractTrees = "1520ce14-60c1-5f80-bbc7-55ef81b5835c"
diff --git a/README.md b/README.md
index 75504ce..b8e54b9 100644
--- a/README.md
+++ b/README.md
@@ -130,7 +130,7 @@ Then, you can use a similar interface `addObs!` to generate the tree that stores
 Tree = ObservableTree()
 # all to all spin correlation
 for i in 1:L, j in i + 1:L
-     addObs!(Tree, (U₁Spin.Sz, U₁Spin.Sz), (i, j); name = (:Sz, :Sz))
+     addObs!(Tree, (U₁Spin.Sz, U₁Spin.Sz), (i, j), (false, false); name = (:Sz, :Sz))
 end
 # local moment
 for i in 1:L