Yes, but where does this "Donkey Ride" come from?

The critical reception for my "Donkey Ride" has been positive, thus far. There has been some small confusion regarding the, ahem, "reactionary subtext" of the poem, but acting swiftly and with the aid of an amanuensis, I have put an end to the rumor (perhaps started by an emulator?) that the poem is in any way a squib tossed in the direction of Mr. Arthur Quiller-Couch, or, for that matter, any other fellow traveler. Still--alas, still--while critics are unanimous in their approval, no small controversy has emerged over the question of the fountainhead of my vision. What, they demand, could possibly be the source for this new (that is to say never-before-seen) extrinsic phantasm? "Surely," as one critic fleered, "Mr. Kaplan is not asking us to ponder Wittgenstein, again?" I should retort the origins of that statement are obvious, and I am not, I repeat not going for that bait, again. Ha, ha, ha. Really, my friends, while it is usually incumbent upon the literary artist to smile coquettishly and demure when prodded to reveal the source of his inspiration, I think I should (to confound my nemesis, if nothing else) break the rule this one time and hint, and not without some indication, that the muse which moves my pen in the case of my animal poetry, at least as it concerns six-legged subjects, is in fact Italian composer Antonio Vivaldi.

But wait, a donkey has only four?

Ah, but does it!