Hellman on mereology in mathematics

I generally admire the work of Geoffrey Hellman, so I was excited to read his preprint titled Mereology in Philosophy of Mathematics, to be included in Handbook of Mereology. While the paper is well-written and quite informative, I find it highly disappointing in terms of whom it gives credit to.

When talking about using mereology in metatheory in order to describe the syntax of a given system, Hellman writes:
In their "Steps Toward a Constructive Nominalism", Goodman and Quine used mereology along with a short list of syntactic primitive predicates of concrete marks or inscriptions intended to reconstruct enough formal syntax of mathematical language to serve as the basis of a formalist, nominalistic account of mathematics as a symbolic, rule-governed activity...
thus crediting Goodman and Quine with this approach. (Goodman and Quine are also often wrongly credited with the formulation of Mereology). Nowhere in his paper does Hellman mention Stanislaw Lesniewski, a Polish logician who actually formulated Mereology and applied it in his metatheoretic description of the syntax of his logical systems motivated by nominalism some, I don't know,  thirty years before Goodman and Quine's  Steps towards constructive nominalism.

I understand that being educated in English-speaking institutions only will result in some bias, but I do fail to understand why a survey on mereology in philosophy of mathematics completely fails to mention the guy who formulated mereology with the intention of constructing foundations of mathematics and spent most of his research working on this stuff.