问从wordpress数据库获取自定义post类型数据，并按季度显示

EN

$ref_month = '';
$args = array(
            'post_type' => 'email_newsletter',
            'paged' => get_query_var('paged')/*,
            'posts_per_page' => -1*/
        ); ?>
<?php   

    $nbemails = new WP_Query($args); 
?>
    <?php if($nbemails->have_posts()) : ?>
     <div class="newsletter-list-container page-container ">
        <div class="row">
            <div class="small-12 medium-12 column">
        <?php while($nbemails->have_posts()) : $nbemails->the_post(); 

                if( get_the_date('mY') != $ref_month ) { 
                    if( $ref_month ) echo "\n".'</ul>';
                    echo "\n".'<h3 class="heading_H3">'.get_the_date('F Y').'</h3>';
                    echo "\n".'<ul class="nl-list">';
                    $ref_month = get_the_date('mY');
                }

            echo "\n".'   <li><a href='.get_permalink($post->ID).'>'.get_the_title($post->ID).' <span class="nl-date">'.get_the_date('F d, Y').'</span></a></li>';
        ?>
                <!-- <a href="<?php the_permalink() ?>"><?php the_title(); ?></a> -->
        <?php 
            endwhile; 
            echo "\n".'</ul>';
        ?>