that is not the correct way to provide source link, please provide link to the page where you download the images.
with the link you have given, how could we know if the images is under public domain or CC0, we could never know if you have the rights to use them commercially.
if you need example, check how i provided source link here in MY CONTRIBUTION
Thank you for your help.
I will not make this mistake again.
I updated. :)