diff --git a/README.md b/README.md
index a1bec2a..0ddf24a 100644
--- a/README.md
+++ b/README.md
@@ -52,7 +52,7 @@
 * [**C#**: _How To: Augmented Reality App Tutorial for Beginners with Vuforia and Unity 3D_](https://www.youtube.com/watch?v=uXNjNcqW4kY) [video]
 * [**C#**: _How To Unity ARCore_](https://www.youtube.com/playlist?list=PLKIKuXdn4ZMjuUAtdQfK1vwTZPQn_rgSv) [video]
 * [**C#**: _AR Portal Tutorial with Unity_](https://www.youtube.com/playlist?list=PLPCqNOwwN794Gz5fzUSi1p4OqLU0HTmvn) [video]
-* [**C#**: _How to create a Dragon in Augmented Reality in Unity ARCore_](https://fr-film.net/v-how-to-create-a-dragon-in-augmented-reality-in-unity-arcore-tutorial-qTSDPkPyPqs.html) [video]
+* [**C#**: _How to create a Dragon in Augmented Reality in Unity ARCore_](https://www.youtube.com/watch?v=qTSDPkPyPqs) [video]
 * [**C#**: _How to Augmented Reality AR Tutorial: ARKit Portal to the Upside Down_](https://www.youtube.com/watch?v=Z5AmqMuNi08) [video]
 * [**Python**: _Augmented Reality with Python and OpenCV_](https://bitesofcode.wordpress.com/2017/09/12/augmented-reality-with-python-and-opencv-part-1/)
 
@@ -69,7 +69,7 @@
 * [**ATS**: _Functional Blockchain_](https://beta.observablehq.com/@galletti94/functional-blockchain)
 * [**C#**: _Programming The Blockchain in C#_](https://programmingblockchain.gitbooks.io/programmingblockchain/)
 * [**Crystal**: _Write your own blockchain and PoW algorithm using Crystal_](https://medium.com/@bradford_hamilton/write-your-own-blockchain-and-pow-algorithm-using-crystal-d53d5d9d0c52)
-* [**Go**: _Building Blockchain in Go_](https://jeiwan.cc/posts/building-blockchain-in-go-part-1/)
+* [**Go**: _Building Blockchain in Go_](https://jeiwan.net/posts/building-blockchain-in-go-part-1/)
 * [**Go**: _Code your own blockchain in less than 200 lines of Go_](https://medium.com/@mycoralhealth/code-your-own-blockchain-in-less-than-200-lines-of-go-e296282bcffc)
 * [**Java**: _Creating Your First Blockchain with Java_](https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa)
 * [**JavaScript**: _A cryptocurrency implementation in less than 1500 lines of code_](https://github.com/conradoqg/naivecoin)
@@ -301,8 +301,6 @@
 * [**Pascal**: _Let's Build a Compiler_](https://compilers.iecc.com/crenshaw/)
 * [**Python**: _A Python Interpreter Written in Python_](http://aosabook.org/en/500L/a-python-interpreter-written-in-python.html)
 * [**Python**: _lisp.py: Make your own Lisp interpreter_](http://khamidou.com/compilers/lisp.py/)
-* [**Python**: _Simple Iterator-based Parsing_](http://effbot.org/zone/simple-iterator-parser.htm)
-* [**Python**: _Simple Top-Down Parsing in Python_](http://effbot.org/zone/simple-top-down-parsing.htm)
 * [**Python**: _How to Write a Lisp Interpreter in Python_](http://norvig.com/lispy.html)
 * [**Python**: _Let’s Build A Simple Interpreter_](https://ruslanspivak.com/lsbasi-part1/)
 * [**Python**: _Make Your Own Simple Interpreted Programming Language_](https://www.youtube.com/watch?v=dj9CBS3ikGA&list=PLZQftyCk7_SdoVexSmwy_tBgs7P0b97yD&index=1) [video]
@@ -340,7 +338,6 @@
 * [**C**: _Writing a UNIX Shell_](https://indradhanush.github.io/blog/writing-a-unix-shell-part-1/)
 * [**C**: _Build Your Own Shell_](https://github.com/tokenrove/build-your-own-shell)
 * [**Go**: _Writing a simple shell in Go_](https://sj14.gitlab.io/post/2018-07-01-go-unix-shell/)
-* [**Ruby**: _A Unix Shell in Ruby_](https://www.jstorimer.com/blogs/workingwithcode/7766107-a-unix-shell-in-ruby)
 * [**Rust**: _Build Your Own Shell using Rust_](https://www.joshmcguigan.com/blog/build-your-own-shell-rust/)
 
 #### Build your own `Template Engine`
@@ -421,7 +418,7 @@
 * [**Nim**: _Writing a INI Parser_](https://xmonader.github.io/nimdays/day05_iniparser.html)
 * [**Nim**: _Writing a Link Checker_](https://xmonader.github.io/nimdays/day04_asynclinkschecker.html)
 * [**Nim**: _Writing a URL Shortening Service_](https://xmonader.github.io/nimdays/day07_shorturl.html)
-* [**Node.js**: _Build a static site generator in 40 lines with Node.js_](https://www.webdevdrops.com/build-static-site-generator-nodejs-8969ebe34b22/)
+* [**Node.js**: _Build a static site generator in 40 lines with Node.js_](https://www.webdevdrops.com/en/build-static-site-generator-nodejs-8969ebe34b22/)
 * [**Node.js**: _Building A Simple Single Sign On(SSO) Server And Solution From Scratch In Node.js._](https://codeburst.io/building-a-simple-single-sign-on-sso-server-and-solution-from-scratch-in-node-js-ea6ee5fdf340)
 * [**Node.js**: _How to create a real-world Node CLI app with Node_](https://medium.freecodecamp.org/how-to-create-a-real-world-node-cli-app-with-node-391b727bbed3)
 * [**PHP**: _Write your own MVC from scratch in PHP_ ](https://chaitya62.github.io/2018/04/29/Writing-your-own-MVC-from-Scratch-in-PHP.html)