fours

this is an illustration i did for a magazine but i got problems with the photos i use, so i have to change it again

now i have a question, since i merely cut the images from random magazines and newspaper if i cannot credit them (because i don't know them) would that mean i cannot use my artwork for commercial purposes? i especially address this to handmade mix media artist or just anyone who can advice me.
i think i have a rough idea how it works for digital collages but does the same law applies to handmade mix medias?

enlightenment would be very much appreciated
thanks