diff --git a/books/free-programming-books-id.md b/books/free-programming-books-id.md
index 91d35f48..3f3aec01 100644
--- a/books/free-programming-books-id.md
+++ b/books/free-programming-books-id.md
@@ -18,6 +18,7 @@
 * [PHP](#php)
 * [Python](#python)
 * [React](#react)
+* [Solidity](#solidity)
 * [TypeScript](#typescript)
   * [Angular](#angular)
   * [Deno](#deno)
@@ -153,6 +154,11 @@
 * [React JS Untuk Pemula](https://masputih.com/2021/05/ebook-gratis-reactjs-untuk-pemula) *(Membutuhkan akun Leanpub atau email yang valid)*
 
 
+### Solidity
+
+* [Smart Contract Blockchain pada E-Voting](https://www.researchgate.net/publication/337961765_Smart_Contract_Blockchain_pada_E-Voting) - Ajib Susanto (HTML, PDF)
+
+
 ### TypeScript
 
 * [Belajar TypeScript](https://leanpub.com/belajar-typescript) *(Membutuhkan akun Leanpub atau email yang valid)*
diff --git a/casts/free-podcasts-screencasts-id.md b/casts/free-podcasts-screencasts-id.md
index 5f023196..27703cf4 100644
--- a/casts/free-podcasts-screencasts-id.md
+++ b/casts/free-podcasts-screencasts-id.md
@@ -1,3 +1,4 @@
 ### Podcast
 
 * [Ceritanya Developer Podcast](https://anchor.fm/ceritanya-developer) (Podcast)
+* [Devmuslim Podcast](https://anchor.fm/devmuslimid) (Podcast)
diff --git a/courses/free-courses-id.md b/courses/free-courses-id.md
index caa65855..5927c8a2 100644
--- a/courses/free-courses-id.md
+++ b/courses/free-courses-id.md
@@ -353,6 +353,7 @@
 ### Solidity
 
 * [Ethereum Blockchain Tutorial Bahasa Indonesia](https://www.youtube.com/playlist?list=PLNl8QwXqW_lvWSc3n3geFSbBtmJvEl4nz) - Odoo Indonesia vITraining
+* [Tutorial Blockchain Bahasa Indonesia](https://www.youtube.com/playlist?list=PLH1gH0TmFBBhvZi4kEqU6kCjyv_y8qBae) - Ipung DEV Academy (YouTube)
 
 
 ### TypeScript