How to Display Results of WP_Post Wrapper for Plugin GC Sermons

I'm using GC Sermons, a WordPress plugin available on GitHub.

It has a wrapper for the WP_Post class called GCS_Sermon_post.

I have successfully retrieved some field values from it:

$sermon = gc_get_sermon_post( $sermon_post_id );
$video_player = $sermon->get_video_player();
echo $video_player;
$excerpt = $sermon->loop_excerpt();
echo $excerpt;

But then I try to use the function get_others_in_series() and it returns errors:

$others_in_series = $sermon->get_others_in_series();

The results are an array, but I don't know how to access them. Any help appreciated.

This is relating to a specific wrapper for WP_Post, but my guess is that general WP_Post principles are applicable.

via Chebli Mohamed