This shelf range caught my eye as I was waiting for the compact shelving to open, and one of the titles looked a bit out of place. But it wasn’t!
Sex in public : the incarnation of early Soviet ideology / Eric Naiman. (OCLC #35450552)
Not that we depend solely on the title for discovery; the record also has two good subject headings:
651 _0 ǂa Soviet Union ǂx History ǂy 1917-1936. 650 _0 ǂa Communism and sex ǂz Soviet Union.
and has been classed with other books about the first one (DK266 = History, Soviet Regime), though depending on the actual content of the book, it could also reasonably go under HX550.S49 (Communism and sex).