Is it better to use "a" or "the" here in my book?

I have a peculiar situation, I am not sure whether to use "a" or "the" in my book. This takes place in a footnote of the title of the work that I mention.

Mario wrote the work "Principia de mathematica"[1] in 1920.

[1] The titles of the work contain "principiae", "principea" and "prinkepia";a/the title with "prinkepia", for example, is provided in the work "Buhaha" by John Firaldo in p.23.

That is - there are many variations of this work's title. Then I provide an example of one of these titles.

So should I write "a title" or "the title"?

Any help is appreciated.