From a2562c3d4060b232c7ebfad802398fb6b6940d44 Mon Sep 17 00:00:00 2001
From: shwetab17 <70053804+shwetab17@users.noreply.github.com>
Date: Fri, 30 Apr 2021 09:32:23 +0530
Subject: [PATCH] updated the bash reference (#5355)

* Update free-programming-books.md

* Update free-programming-books.md
---
 books/free-programming-books.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/books/free-programming-books.md b/books/free-programming-books.md
index f24290bd3..09cd7a6d2 100644
--- a/books/free-programming-books.md
+++ b/books/free-programming-books.md
@@ -1091,6 +1091,7 @@ Kerridge (PDF) (email address *requested*, not required)
 * [BashGuide](http://mywiki.wooledge.org/BashGuide) - Maarten Billemont (HTML) [(PDF)](http://s.ntnu.no/bashguide.pdf)
 * [Conquering the Command Line](http://conqueringthecommandline.com/book/frontmatter) - Mark Bates (HTML)
 * [Getting Started with BASH](http://www.hypexr.org/bash_tutorial.php) (HTML)
+* [GNU Bash manual](https://www.gnu.org/software/bash/manual/bash.pdf) (PDF)
 * [Google Shell Style Guide](https://google.github.io/styleguide/shell.xml) - Paul Armstrong (HTML)
 * [Introduction to Bash Scripting](https://github.com/bobbyiliev/introduction-to-bash-scripting) - Bobby Iliev (Markdown, PDF)
 * [Introduction to the Command Line](https://launchschool.com/books/command_line) - Launch School (HTML)