Used to add content to the single book page.
Example:
/**
* Add text after the book information
*
* @param int $book_id
*
* @return void
*/
function add_content_after_novelist_info( $book_id ) {
?>
Your text or HTML here.
<?php
}
add_action( 'novelist/book/after-content', 'add_content_after_novelist_info', 20 );