Shortcode to display WordPress Menu

functions.php

<?php
/**
 * Shortcode to display a WordPress menu
 *
 */
function theme_slug_menu_shortcode( $atts ) {

	// Get Shortcode Parameters.
	$menu = shortcode_atts( array(
		'slug'  => '',
	), $atts );

	// Return Custom Menu.
	return wp_nav_menu( array(
		'menu'       => $menu['slug'],
		'menu_class' => 'artikelserie',
		'echo'       => false,
		'items_wrap' => '<ol id="%1$s" class="%2$s">%3$s</ol>',
	) );

}
add_shortcode( 'custom_menu', 'theme_slug_menu_shortcode' );