Lacassin, Francis. 1972. The Comic Strip and Film Language. Film Quarterly, 26(1), 11-23.
In this piece translated by David Kunzle, French theorist Francis Lacassin discusses the similarities between the "syntax" of film and comics, noting that they both use "shots" as their base units. For him, this includes various things, like various degrees of framing (long shot, close up, medium shot), dynamic use of what could be multipanel representations ("panning"), as well as semantic alterations, like subjective viewpoints. (I would argue that this isn't "syntax" at all... but that's a larger post).
He argues that though film and comics emerged around the same time, these techniques came first in comics — not the other way around, as is often argued — and that they may have been autonomous developments not influencing each other at all.
He writes: "It is more reasonable to suppose that comic strip and cinema have both separately drawn the elements of their respective languages from the common stock accumulated in the course of the centuries by the plastic and graphic arts." (14)
To this I would question, is it really through historical development, or is this just a reflection of the structuring of people's minds/brains?
He hypothesizes also that film and comics both accomplish their sequential meaning by use of the film theory of montage, which for Lacassin appears to cover most things that do not appear similar to real-world perception.
In his own section at the end, Kunzle criticizes Lacassin for claiming comics were invented before cinema, while those framing techniques are cited being used by authors two generations before that "birth" of comics. Kunzle then discusses the work of 1800s artists Töpffer, Doré, and Busch, noting that they used various techniques like close-ups and polymorphic representation (where one character is repeated in a single frame showing the unfolding of action), among others.