CODOH hosts a copy of "The Ruins of the Gas Chambers: A Forensic Investigation of Crematoriums at Auschwitz I and Auschwitz-Birkenau".
https://codoh.com/library/document/the- ... -forensic/
However even after extracting the image files directly from that PDF, they seem to be of a lower resolution and quality than those on the Holocaust History Project website. So the below images are direct linked from there.
https://phdn.org/archives/holocaust-his ... les1.shtml

"Figure 1a. Aerial photograph of the gas chamber in Crematorium II (courtesy of Wojciech Gorgolewski)."

"Figure 8b. Area of Zyklon Hole 1, Crematorium II. Tarpaper separating concrete layer below and sand-cement layer above is visible. South to north view."

"Figure 9. Hole cut for unknown purpose in Crematorium II roof, likely after liberation in January 1945."

"Figure 11a. First (southernmost) Zyklon hole, overview. Taken from east looking west. Observe square form, with no rebar present; although damaged in explosion, hole clearly visible."

"Figure 11b. First (southernmost) Zyklon hole, detail. Taken from below, showing residue of dripping tar. Surviving crawl space approx. three feet here."

"Figure 12. Second (from south) Zyklon hole, east to west view. Chunk of concrete torn away by explosion lies atop northern edge; western edge completely shattered. Outline of hole superimposed."

"Figure 13. Straight edge and inward-bent rebar on southern side of second Zyklon hole. Such bending could not result from the explosion, which lifted the roof upwards."

"Figure 14. Inwardly bent rebar at north and east edges of second Zyklon hole, partially destroyed in explosion."

"Figure 15. West-east view of hypothesized location of third Zyklon hole."

"Figure 16. Remains of fourth (seen from south) Zyklon hole. Rebar skirts two sides, ends at other two sides bent inward and looped back. Note rotated roof slab showing formwork on inner side."

"Figure 18b. Rebar stretched to a point at Zyklon hole 1, Crematorium II."