Dear Patrick,
 If the story were true that "the corpses of 750,000 to three million murdered Jews (the numbers depending on the author) were first buried in mass graves, but then, following the spring of 1943, dug up and cremated in open air on huge gratings" there would be evidence today of massive holes in the ground that had been dug, filled with bodies, covered, re-excavated, and refilled.
 Ground penetrating radar is a standard industrial technique for discovering the location of graves, i.e. holes in the ground that have been dug and covered with dirt.
 All the people who believe that "the corpses of 750,000 to three million murdered Jews (the numbers depending on the author) were first buried in mass graves, but then, following the spring of 1943, dug up and cremated in open air on huge gratings" had to do to prove that the people in the cited article are liars was to pull out a credit card and rent a ground penetration radar device and find the allegedly missing holes.
 They have had five years to find their credit cards.
 I suggest that interested persons search Google for "Treblinka ground penetrating radar" and come to their own conclusions.
 There is more to history that "Holocaust" movies.
Dad
 
 
 
 http://vho.org/tr/2004/1/Graf97-101.html
 Our interest in Treblinka was renewed by the end of 1999, when our Australian friend Fredrick Toben informed us of the ground-penetrating radar investigations by his fellow Australian Richard Krege, a young engineer. By means of radar, which discovers irregularities of the soil structure and can indicate underground finds as buried objects and grave sites, Krege investigated the area of Treblinka, which, according to eyewitnesses, contained huge mass graves. Since neither Treblinka, nor Belzec, Sobibor, or Chelmno are alleged to have had crematoria, the corpses of 750,000 to three million murdered Jews (the numbers depending on the author) [would have to have been] buried in mass graves, but then, following the spring of 1943, dug up and cremated in open air on huge gratings, allegedly without leaving a trace. Based on preliminary results from several days worth of radar investigations in October 1999, Krege came to the conclusion that the soil in the zone of the alleged mass graves was completely untouched and that therefore the graves had never existed.
 
 .....
 
 This was exciting news. If Krege’s results were correct, then the extermination camp story was, with absolute scientific certainty, finished, for the official version of Treblinka stands and falls with the existence of those graves. I quickly contacted the Australian engineer by telephone in order to learn the details. He informed me that his data were incomplete: Further on-site investigations were necessary....