How do I make a book part of a series

I just added the new Billy Boyle novel, Proud Sorrows, to my collection. It is #18 in the Billy Boyle series by James Benn, but it doesn't show as being part of the series and I can't find a place to add it.

Proud Sorrows

If you scroll down the main work page you will find a section called 'Series and work relationships'.

Billy Boyle

Or you can scroll down the series page to edit the series and add the book there.

>From the work page here -> https://www.librarything.com/work/30047162/249236055 scroll down until you see "Series and work relationships" then click the Add/Edit. Click the Same Author tab to bring up the series list for that author for quicker adding.

ETA: you might also want to read through https://wiki.librarything.com/index.php/HelpThing:Series

Many thanks!