Articles
http://www.thegeekstuff.com/2009/03/15-practical-unix-grep-command-examples/
https://www.cyberciti.biz/faq/howto-use-grep-command-in-linux-unix/
https://www.tutorialspoint.com/unix_commands/grep.htm
https://www.techonthenet.com/linux/commands/grep.php
https://www.computerhope.com/unix/ugrep.htm
http://www.thegeekstuff.com/2009/03/15-practical-unix-grep-command-examples/
https://www.cyberciti.biz/faq/howto-use-grep-command-in-linux-unix/
https://www.tutorialspoint.com/unix_commands/grep.htm
https://www.techonthenet.com/linux/commands/grep.php
https://www.computerhope.com/unix/ugrep.htm
