Yes, and Vincent Salandria and James W. Douglass.
A lot of smart guys are in the aforementioned, but...the ideology writes the agenda, and the agenda writes the narrative.
Another smart guy, and former CIA director with decades of experience in international affairs, James Woolsey, suspects the KGB.
Some suspect the Mafia or LBJ.
I suspect, but concede it is only a reasonable suspicion, that G2'ers were involved, although possibly just Alpha-66'ers.
A very small plot, involving LHO and two others.
Strange JFKA Fact: Almost no one believes LHO was part of a small, informal, ad hoc JFKA, consisting of lower level G2'ers or Cuban exiles.
LHO is usually posited to have been totally innocent, and framed in plot involving dozens and dozens up to the highest levels somewhere...or to have acted alone.
Then, we have crackpots positing Mossad...oh never mind.