A few notes while we await Halibutt book review (and given that I have worked with Halibutt for almost a year on Wikipedia, I have no doubt it will be a good and impartial review).
Note 1: Polish-Soviet War was a taboo in the communists time. It meant not only that you there was virtually no research going on for 50 (70 in case of USR) years, but that one could go to prison for disscussing it. Thus majority of useful publications in that area were done on the West, based mostly on pre-IIWW Polish sources. Which means that majority of publications relevant to PSW are, suprisingly, often written first in English and then retranslated into Polish or Russian. What is strange, then, is that no such findings were publicized (*discovered*) in English earlier, although there has always been a pro-leftist/communist/Soviet movement in the West, which would have surely used this in publications regarding PSWar and KAtyn. Makes one wonder why absolutely none of the Western historians writing about this period (A J Taylor, Norman Davies, et al) wrote about this. Neither do I recall any major findings surfacing after 1990s neither in Poland nor Russia, and given the current Russian government policy of subjugating historical findings to political needs (Anty-Katyn...how sad, how familiar...), I have would approach any Sovie...Russian new revelations and sources with some doubt. Especially as the talk about Polish POW camps has surfaced, accidentally, at the same time as the Katyn Anniversairy and Polish involvement in the Oragne Revolution in Ukraine.
Note 2:This does not mean, of course, that Soviet POWs didn't die in Polish camps. They died - but from ilness, not any executions. Polish government - and do remember that it was formed just on the eve of the war, in 1918, on a territories belonging to 3 former empires, ravaged by 4 years of IWW, and was engaged in conflicts on all borders (including a war for survival with bolsheviks) - was unable to provide much medicine and healthcare, as what resources it could was first directed to Polish civilian and military hospital. POW camps received whatever was left, thus no wonder that the rampaging post-IWW Spanish Flu claimed a rather disproportianaly high casualties in POW camps. I am sure that Poles in SU camps suffered similarly, as did various POWs from many smaller conflicts in Central/Eastern Euroope, that erupted in the wake of German withdrawal from Ober-Ost.
Note 3: I am pretty sure Polish army requisitioned food, horses and anything they needed - in Ukraine, Poland, or elsewhere. Same as Red Army did. This was war, and when supplies got scarce (and neither side had good supply lines), the local population would suffer. It is a sad constant of war.
Note 4: Ummm. Is this a joke?
The author also mentions a report of certain "RFSR representative to Warsaw", who on January 5th, 1922, wrote that "overnight of 18th - 19th of December there was a systematical slaughter of Russian POWs and citizens in the camp (in of Strzałkowo - Halibutt). It came down to shooting at the barracks, and in the result one prisoner, Korney Kalita who was sleeping in his bed was wounded.
A systematic slaughter (...) in the result one prisoner (...) was wounded.
Note 5: Ukraine was neither Polish nor Soviet/Russian. At first it was invaded by both Poles and the Soviets, and thus Poles were the invaders (although one should remember that while Ukraine countryside was dominantly Ukrainian, their cities had mostly a major Polish population, thus the struggle for Lwow and such). However, after Ukrainian goverment (of Peltura) signed a treaty with Poland, one can hardly refer to Poles as invaders/occupiers - unless somebody follows the Soviet logic 'truth is what is useful for us, same with logic and such irrelevant concept, viva propaganda, communism will triumph' :>
Note 6: There was, of course, pro-Soviet Ukrainian government, as well as a pro-Soviet Polish division (or 2-3) fighting in the Red Army, that believed in the commies cause, and fought for the worldwide revolution, Red Ukraine Soviet Republic and Red Poland Soviet Republic. Same with Lithuanian and others. In both cases, they commanded a much smaller forces then their pro-national (an important distinguishing point - Poland and Peltura's Ukrainians fought for a sovereign, democratic state, while bolshevicks codemned the very ideals like nationality or democracy), so I don't think we can make a point of Ukrainina Cilvil War (and most certainly not Polish Civil War). It was, at first, after German withdrawal from Ober-Ost, in 1918-1919, a giant free for all border conflict, and later, in 1920, the Polish-Soviet all out war (that nobody planned and happened 'by accident' - a very interesting war that was...).
Note 7: Well, ok, in 1920 there was also the Polish-Lithuanian border conflict, but it was not really a war. There were border conflicts aplanty in C/E Europe in those years, from Germany/Poland and Italy/Hungary (or Romania, I don't remember) border in the east to Balkan conflicts in the south to Baltic conflicts in the north. But only the PSW was the real, major war, both in terms of fighting personell and victory consequences (just think what would happen if Soviets had won....).