diff --git a/books/free-programming-books-langs.md b/books/free-programming-books-langs.md
index f5add4adf..da2ff5112 100644
--- a/books/free-programming-books-langs.md
+++ b/books/free-programming-books-langs.md
@@ -2377,6 +2377,7 @@ Books on general-purpose programming that don't focus on a specific language are
 * [Essential Scala](http://underscore.io/books/essential-scala/) - Noel Welsh, Dave Gurnell (PDF, HTML, EPUB) (email address *requested*, not required)
 * [Functional Programming for Mortals](https://leanpub.com/fpmortals/read) - Sam Halliday
 * [Functional Programming, Simplified (Scala edition)](https://alvinalexander.com/photos/functional-programming-simplied-free-pdf-preview) - Alvin Alexander (free preview (400 pages from 595), PDF)
+* [Hands-on Scala](https://github.com/handsonscala/handsonscala)
 * [Hello, Scala](https://alvinalexander.com/photos/hello-scala-free-pdf-preview) - Alvin Alexander (free preview (120 pages from 257), PDF)
 * [Learning Scala in small bites](http://matt.might.net/articles/learning-scala-in-small-bites/)
 * [Learning Scalaz](http://eed3si9n.com/learning-scalaz/)
@@ -2429,6 +2430,7 @@ Books on general-purpose programming that don't focus on a specific language are
 ### Scilab
 
 * [Introduction to Scilab](http://forge.scilab.org/index.php/p/docintrotoscilab/downloads/)
+* [PHP tutorial](https://www.tutorialspoint.com/php/) - Tutorialspoint
 * [Programming in Scilab](http://forge.scilab.org/index.php/p/docprogscilab/downloads/)
 * [Writing Scilab Extensions](http://forge.scilab.org/index.php/p/docsciextensions/downloads/)
 
diff --git a/more/free-programming-interactive-tutorials-en.md b/more/free-programming-interactive-tutorials-en.md
index 186672b26..4739e6c96 100644
--- a/more/free-programming-interactive-tutorials-en.md
+++ b/more/free-programming-interactive-tutorials-en.md
@@ -276,6 +276,7 @@
 #### Redux
 
 * [Front End Development Libraries: Redux](https://www.freecodecamp.org/learn/front-end-development-libraries/redux) - freeCodeCamp
+* [Redux Official Documentation](https://redux.js.org/introduction/getting-started)
 
 
 #### Svelte
@@ -370,6 +371,7 @@
 ### PostgreSQL
 
 * [PostgreSQL Tutorial](https://www.postgresqltutorial.com)
+* [PostgreSQL Tutorial](https://www.w3schools.com/postgresql/) - W3Schools
 
 
 ### Python