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Referencing from several images is normal so I don't think you need to for several. The rule is if you used one single photo as a reference, to cite it. For photos you took yourself, the detailed rules page under that rule it says

The exception to this rule is if you own the photo reference, or have purchased the rights to them

Ok, so for example my recent post is a commission job and I got a oldtime photo from the 80s sent to me. I also looked at maybe 4 other photos on the internet but it was just to look at some details for a few minutes. Do I need to link the photos?
Thanks for replying :)

I think you should be okay to not list them in that kind of situation :)