I was replying to you too quickly > I don't have much time to look up every example, to try and find the source work... I do not have the source works as text because that would be just too much information to store in any sort of helpful manner... names of composers of the works I already gave you...
I can post examples as midi, I may be able to tell you more names of source works over the coming few days...
if you're suspicious of me, which I only offer because of my previous experiences on the forum, nothing to do with you, I would encourage you in persisting, for my sake...
but for yours to reconsider: why would I try to invent something like this and what motive would it serve?
all the best!
PS another thing that "masks" the ligature well is that, as you can see, it forms a cambiata where "return or recovery is larger than a 2 (secunda) or absent" which is used by this particular composer very often (but a fair number of others as well)
(here I'm just purely speaking "melodically", second tone of the cambiata figure is actually consonant with one voice but has a "genuine dissonant ""function"" of the cambiata figure's second tone" in relation to another...)
as I said it's nearing a cadence so the relations get a bit less straightforward, as I'm sure you know is common...
again, others are much more "plain" / easy to spot