Commas Needed:

The book, Time Between Trains, by Anthony Bukoski, is a collection of short stories.

The book, Where No Gods Came, by Sheila O'Connor, is a novel.

The book, Time Between Trains, is a collection of short stories written by Anthony Bukoski.

The book, Where No Gods Came, is a novel written by Sheila O'Connor.

Anthony Bukoski’s book, Time Between Trains, is a collection of short stories.

Sheila O'Connor's book, Where No Gods Came, is a novel.

In the second short story, “Time Between Trains,” the reader is introduced to Joe Rubin.

Commas Not Needed:

Time Between Trains is a collection of short stories written by Anthony Bukoski.

Where No Gods Came is a novel written by Sheila O'Connor.

Anthony Bukoski’s Time Between Trains is a collection of short stories.

Sheila O'Connor's Where No Gods Came is a novel.

Commas Optional:

Time Between Trains, by Anthony Bukoski, is a collection of short stories.

Time Between Trains by Anthony Bukoski is a collection of short stories.

Where No Gods Came, by Sheila O'Connor, is a novel.

Where No Gods Came by Sheila O'Connor is a novel.

Problematic / Mixed Sentence:

In the book, Time Between Trains, by Anthony Bukoski contains many different short stories.

In the book, Where No Gods Came, by Sheila O'Connor is about Minneapolis in 1973.