PHP Static vs Non-static methods, Laravel
Why use static method in PHP’s laravel model class? http://stackoverflow.com/questions/24879567/why-use-static-method-in-phps-laravel-model-class
Static vs Non-static methods http://www.codedwell.com/post/59/static-vs-non-static-methods-in-php
Does static method in PHP have any difference with non-static method? http://stackoverflow.com/questions/24879567/why-use-static-method-in-phps-laravel-model-class