Text Formatting ⇒ Two horizontal slabs for bilingual editions

[pippipalma]

Hello,
I have to present a text and its translation (spanning several pages) in two horizontal slabs in each page, like in the following example from an old book:

Example.png (254.9 KiB) Viewed 1814 times

I went through the documentation of both parallel and paracol packages, but they only seem to manage parallel columns (i.e., vertical slabs).
Do you have any suggestion on how to manage two parallel horizontal slabs in which the text streams could be synchronised at certain points (using, for example, pairs of \ParallelUpperText and \ParallelLowerText commands)?

Thanks for your help!

Giuseppe