Add back the ver 3.1 download
diff --git a/docs-site/docs/download.md b/docs-site/docs/download.md
index b2ba081..99ec2d7 100644
--- a/docs-site/docs/download.md
+++ b/docs-site/docs/download.md
@@ -1,5 +1,5 @@
 ---
-id: download-singa
+id: downloads
 title: Download SINGA
 ---
 
@@ -18,6 +18,29 @@
 
 You can also check the SHA512 or MD5 values to see if the download is completed.
 
+## V3.1.0 (30 October 2020):
+
+- [Apache SINGA 3.1.0](http://www.apache.org/dyn/closer.cgi/singa/3.1.0/apache-singa-3.1.0.tar.gz)
+  [\[SHA512\]](https://www.apache.org/dist/singa/3.1.0/apache-singa-3.1.0.tar.gz.sha512)
+  [\[ASC\]](https://www.apache.org/dist/singa/3.1.0/apache-singa-3.1.0.tar.gz.asc)
+- [Release Notes 3.1.0](releases/RELEASE_NOTES_3.1.0)
+- Major changes:
+  - Update Tensor core:
+    - Support tensor transformation (reshape, transpose) for tensors up to 6 dimensions.
+    - Implement traverse_unary_transform in Cuda backend, which is similar to CPP backend one.
+  - Add new tensor operators into the autograd module.
+  - Reconstruct sonnx to
+    - Support creating operators from both layer and autograd.
+    - Re-write SingaRep to provide a more powerful intermediate representation of SINGA.
+    - Add a SONNXModel which implements from Model to provide uniform API and features.
+  - Replace the Travis CI with Github workflow. Add quality and coverage management.
+  - Add compiling and packaging scripts to create wheel packages for distribution.
+  - Fix bugs
+    - Fix IMDB LSTM model example training script.
+    - Fix Tensor operation Mult on Broadcasting use cases.
+    - Gaussian function on Tensor now can run on Tensor with odd size.
+    - Updated a testing helper function gradients() in autograd to lookup param gradient by param python object id for testing purpose.
+
 ## V3.0.0 (18 April 2020):
 
 - [Apache SINGA 3.0.0](http://www.apache.org/dyn/closer.cgi/singa/3.0.0/apache-singa-3.0.0.tar.gz)
diff --git a/docs-site/website/sidebars.json b/docs-site/website/sidebars.json
index b35fea1..34e497f 100644
--- a/docs-site/website/sidebars.json
+++ b/docs-site/website/sidebars.json
@@ -17,7 +17,7 @@
       "half-precision"
     ],
     "Development": [
-      "download-singa",
+      "downloads",
       "build",
       "contribute-code",
       "contribute-docs",
diff --git a/docs-site/website/versioned_docs/version-2.0.0/download-singa.md b/docs-site/website/versioned_docs/version-2.0.0/download-singa.md
index c9d3dd3..c1fa985 100644
--- a/docs-site/website/versioned_docs/version-2.0.0/download-singa.md
+++ b/docs-site/website/versioned_docs/version-2.0.0/download-singa.md
@@ -1,7 +1,7 @@
 ---
-id: version-2.0.0-download-singa
+id: version-2.0.0-downloads
 title: Download SINGA
-original_id: download-singa
+original_id: downloads
 ---
 
 <!--- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.  You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.  -->
diff --git a/docs-site/website/versioned_docs/version-3.0.0.rc1/download-singa.md b/docs-site/website/versioned_docs/version-3.0.0.rc1/download-singa.md
index 8bea604..c658a1b 100644
--- a/docs-site/website/versioned_docs/version-3.0.0.rc1/download-singa.md
+++ b/docs-site/website/versioned_docs/version-3.0.0.rc1/download-singa.md
@@ -1,7 +1,7 @@
 ---
-id: version-3.0.0.rc1-download-singa
+id: version-3.0.0.rc1-downloads
 title: Download SINGA
-original_id: download-singa
+original_id: downloads
 ---
 
 <!--- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.  You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.  -->
diff --git a/docs-site/website/versioned_docs/version-3.0.0/download.md b/docs-site/website/versioned_docs/version-3.0.0/download.md
index b05fe49..c34aba3 100644
--- a/docs-site/website/versioned_docs/version-3.0.0/download.md
+++ b/docs-site/website/versioned_docs/version-3.0.0/download.md
@@ -1,7 +1,7 @@
 ---
-id: version-3.0.0-download-singa
+id: version-3.0.0-downloads
 title: Download SINGA
-original_id: download-singa
+original_id: downloads
 ---
 
 <!--- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.  You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.  -->
diff --git a/docs-site/website/versioned_docs/version-3.1.0/download.md b/docs-site/website/versioned_docs/version-3.1.0/download.md
index a08f98a..a423077 100644
--- a/docs-site/website/versioned_docs/version-3.1.0/download.md
+++ b/docs-site/website/versioned_docs/version-3.1.0/download.md
@@ -1,7 +1,7 @@
 ---
-id: version-3.1.0-download-singa
+id: version-3.1.0-downloads
 title: Download SINGA
-original_id: download-singa
+original_id: downloads
 ---
 
 <!--- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.  You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.  -->
@@ -19,6 +19,29 @@
 
 You can also check the SHA512 or MD5 values to see if the download is completed.
 
+## V3.1.0 (30 October 2020):
+
+- [Apache SINGA 3.1.0](http://www.apache.org/dyn/closer.cgi/singa/3.1.0/apache-singa-3.1.0.tar.gz)
+  [\[SHA512\]](https://www.apache.org/dist/singa/3.1.0/apache-singa-3.1.0.tar.gz.sha512)
+  [\[ASC\]](https://www.apache.org/dist/singa/3.1.0/apache-singa-3.1.0.tar.gz.asc)
+- [Release Notes 3.1.0](releases/RELEASE_NOTES_3.1.0)
+- Major changes:
+  - Update Tensor core:
+    - Support tensor transformation (reshape, transpose) for tensors up to 6 dimensions.
+    - Implement traverse_unary_transform in Cuda backend, which is similar to CPP backend one.
+  - Add new tensor operators into the autograd module.
+  - Reconstruct sonnx to
+    - Support creating operators from both layer and autograd.
+    - Re-write SingaRep to provide a more powerful intermediate representation of SINGA.
+    - Add a SONNXModel which implements from Model to provide uniform API and features.
+  - Replace the Travis CI with Github workflow. Add quality and coverage management.
+  - Add compiling and packaging scripts to create wheel packages for distribution.
+  - Fix bugs
+    - Fix IMDB LSTM model example training script.
+    - Fix Tensor operation Mult on Broadcasting use cases.
+    - Gaussian function on Tensor now can run on Tensor with odd size.
+    - Updated a testing helper function gradients() in autograd to lookup param gradient by param python object id for testing purpose.
+
 ## V3.0.0 (18 April 2020):
 
 - [Apache SINGA 3.0.0](http://www.apache.org/dyn/closer.cgi/singa/3.0.0/apache-singa-3.0.0.tar.gz)
diff --git a/docs-site/website/versioned_docs/version-3.1.0_Chinese/download.md b/docs-site/website/versioned_docs/version-3.1.0_Chinese/download.md
index a3e70b6..45eb152 100644
--- a/docs-site/website/versioned_docs/version-3.1.0_Chinese/download.md
+++ b/docs-site/website/versioned_docs/version-3.1.0_Chinese/download.md
@@ -1,7 +1,7 @@
 ---
-id: version-3.1.0_Chinese-download-singa
+id: version-3.1.0_Chinese-downloads
 title: Download SINGA
-original_id: download-singa
+original_id: downloads
 ---
 
 <!--- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.  You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.  -->
diff --git a/docs-site/website/versioned_sidebars/version-2.0.0-sidebars.json b/docs-site/website/versioned_sidebars/version-2.0.0-sidebars.json
index 116f5d6..9359a63 100644
--- a/docs-site/website/versioned_sidebars/version-2.0.0-sidebars.json
+++ b/docs-site/website/versioned_sidebars/version-2.0.0-sidebars.json
@@ -22,7 +22,7 @@
       "version-2.0.0-model-zoo-imagenet-vgg"
     ],
     "Development": [
-      "version-2.0.0-download-singa",
+      "version-2.0.0-downloads",
       "version-2.0.0-build",
       "version-2.0.0-contribute-code",
       "version-2.0.0-contribute-docs",
diff --git a/docs-site/website/versioned_sidebars/version-3.0.0-sidebars.json b/docs-site/website/versioned_sidebars/version-3.0.0-sidebars.json
index 06aa553..54fa55b 100644
--- a/docs-site/website/versioned_sidebars/version-3.0.0-sidebars.json
+++ b/docs-site/website/versioned_sidebars/version-3.0.0-sidebars.json
@@ -14,7 +14,7 @@
       "version-3.0.0-dist-train"
     ],
     "Development": [
-      "version-3.0.0-download-singa",
+      "version-3.0.0-downloads",
       "version-3.0.0-build",
       "version-3.0.0-contribute-code",
       "version-3.0.0-contribute-docs",
diff --git a/docs-site/website/versioned_sidebars/version-3.0.0.rc1-sidebars.json b/docs-site/website/versioned_sidebars/version-3.0.0.rc1-sidebars.json
index 982c16a..1705bfa 100644
--- a/docs-site/website/versioned_sidebars/version-3.0.0.rc1-sidebars.json
+++ b/docs-site/website/versioned_sidebars/version-3.0.0.rc1-sidebars.json
@@ -13,7 +13,7 @@
       "version-3.0.0.rc1-dist-train"
     ],
     "Development": [
-      "version-3.0.0.rc1-download-singa",
+      "version-3.0.0.rc1-downloads",
       "version-3.0.0.rc1-build",
       "version-3.0.0.rc1-contribute-code",
       "version-3.0.0.rc1-contribute-docs",
diff --git a/docs-site/website/versioned_sidebars/version-3.1.0-sidebars.json b/docs-site/website/versioned_sidebars/version-3.1.0-sidebars.json
index 02acb94..3331fc4 100644
--- a/docs-site/website/versioned_sidebars/version-3.1.0-sidebars.json
+++ b/docs-site/website/versioned_sidebars/version-3.1.0-sidebars.json
@@ -16,7 +16,7 @@
       "version-3.1.0-time-profiling"
     ],
     "Development": [
-      "version-3.1.0-download-singa",
+      "version-3.1.0-downloads",
       "version-3.1.0-build",
       "version-3.1.0-contribute-code",
       "version-3.1.0-contribute-docs",
diff --git a/docs-site/website/versioned_sidebars/version-3.1.0_Chinese-sidebars.json b/docs-site/website/versioned_sidebars/version-3.1.0_Chinese-sidebars.json
index c8a9594..d07516a 100644
--- a/docs-site/website/versioned_sidebars/version-3.1.0_Chinese-sidebars.json
+++ b/docs-site/website/versioned_sidebars/version-3.1.0_Chinese-sidebars.json
@@ -16,7 +16,7 @@
       "version-3.1.0_Chinese-time-profiling"
     ],
     "Development": [
-      "version-3.1.0_Chinese-download-singa",
+      "version-3.1.0_Chinese-downloads",
       "version-3.1.0_Chinese-build",
       "version-3.1.0_Chinese-contribute-code",
       "version-3.1.0_Chinese-contribute-docs",