Russian dopers: Is (or was) “сноск” a correct inflection of “сноска”?

Factual Questions
1

In a Word Ways article (subscription required) I came across a claim that “сноск” is the “genitive plural zero ending” form of the word “сноска” (English: footnote). The author claims this information is from the 1960 edition of Ozhegov’s Dictionary of the Russian Language (Словарь русского языка).

However, a Russian speaker I know is insistent that this claim is incorrect, and that the only correct genitive form of “сноска” is “сносок”.

A Google search for “сноск” doesn’t turn up any uses which can’t be discounted as typos for “сноска” or other forms. We also can’t find the form “сноск” in any online dictionary which gives inflectional tables. Can anyone here confirm whether the form “сноск” is actually attested anywhere in print, or would have been considered proper Russian in 1960?

2

IANARD - but I do speak Russian. If it is сноск, that certainly would be irregular. This site which purports to be the 1992 Ozhegov in .txt format does not mention an irregular genitive plural so I would be inclined to go with the Russian speaker you know.

3

Or a dictionary. I checked two. One didn’t specify, but the other said that *сносок *is the correct genitive plural. Zero ending, yes, but with the floating vowel that doesn’t appear in the nominative. (In other words, assuming сноск is quite an easy mistake to make.)