Warning: Before anything else first I want to tell you, some dark web links have mind disturbing content, fraudulent, unpleasant content, porn, child porn, Drugs, Weapons, Gadgets buying and selling, and more horrible things. That’s why you are the only one person who is responsible for your all activity; We are not recommending any dark web sites here, If you lose or damaged anything then we are not responsible for these. Here I am adding these links only for education and research purpose.
Because the act of linking to a site does not imply ownership or endorsement, you do not need to ask permission to link to a site that is publicly accessible. For example, if you found a site's URL through a search engine, then linking to it shouldn't have legal ramifications. There have been one or two cases in the U.S. that implied that the act of linking without permission is legally actionable, but these have been overturned every time.
To prevent users from linking to one version of a URL and others linking to a different version (this could split the reputation of that content between the URLs), focus on using and referring to one URL in the structure and internal linking of your pages. If you do find that people are accessing the same content through multiple URLs, setting up a 301 redirect32 from non-preferred URLs to the dominant URL is a good solution for this. You may also use canonical URL or use the rel="canonical"33 link element if you cannot redirect.
It appears that the reason this page from a little-known website is able to rank amongst the bigger players is that the content itself is more focussed. It talks about how to name images for SEO, whereas most of the other pages are more general guides to image SEO—which all presumably mention the importance of naming images correctly, amongst other things.