Uncaught ReferenceError: jQuery is not defined

Hi, at one of my sites ( http://bit.ly/2eKNRwv ) there is still "Uncaught ReferenceError: jQuery is not defined", how I can solve it?

If you check the code, it should be alright, right?

I'm including the script following way:

function mh_newsdesk_child_styles() {
    wp_enqueue_style('mh-newsdesk-parent-style', get_template_directory_uri() . '/style.css');
    wp_enqueue_style('mh-newsdesk-child-style', get_stylesheet_directory_uri() . '/style.css', array('mh-newsdesk-parent-style'));
    wp_enqueue_script('custom-jquery', get_stylesheet_directory_uri() . '/custom.js', array('jQuery'), true);
add_action('wp_enqueue_scripts', 'mh_newsdesk_child_styles');

What is wrong? Thanks a lot!