Custom Book Reviews Archive Page

I wanted an archive page for my book reviews that showed, for each book, its front cover and an excerpt of the review.

/**
* Template Name:  Book Reviews Template
* Description:  Used as a page template to show page contents, followed by a loop
* through the Book Review (book-reviews) Category
*/

add_action('genesis_loop', 'zoia_book_reviews_loop');

function zoia_book_reviews_loop() {

    $args = array(
        'category_name' => 'book-reviews',  // category slug
        'order_by' => 'post_date',
        'order' => 'DESC',
        'posts_per_page' => '10',
    );

    $loop = new WP_Query($args);

    if($loop->have_posts()) {

        while ($loop->have_posts() ): $loop->the_post();
             echo '
';
             echo '
';

        if(has_post_thumbnail()) {
             echo ''">';
             the_post_thumbnail('medium');
             echo '';
        } else {
             echo ' ';
        }
        echo '
';

        $summary = get_the_excerpt();
        $summary = str_replace('Buy from Amazon', '', $summary);

        echo '
';
        echo '
'">' . get_the_title() . '
';
        echo '
' . $summary . '
';
        echo '
';
        echo '
';
        endwhile;

    }
    wp_reset_postdata();

}

genesis();
?>