Transitive Property data Categorizatio nquestion

[imaguy77]

I have a list of 2000+ book titles. In our database, we track the previous version of the book. But I want to create a table which shows, for a given title line, all versions of the book. Below is an example of the data table, and below that is an example of the output am looking for. Any recommendations on the best way to do this? Can't think of anything elegant. Thanks!

Current Title	Previous title
2016 A	2015 A
2016 B	2015 B
2016 C	2015 C
2016 D	2015 D
2015 A	2014 A
2015 B	2014 B
2015 C	2014 C
2015 D	2014 D
	Title Line 1	Title Line 2	Title Line 3
GroupA	2016 A	2015 A	2014 A
GroupB	2016 B	2015 B	2014 A
GroupC	2016 C	2015 C	2014 C
etc

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