How to get the resources in the self link of inwardIssue or outwardIssue which is from issulinks

I want to notify all the users involved in the issue update, so I first get the issues in Issuelinks, but they do not provide user information, so I want to get more information through self link, but when I use the HttpGet method to get slef link resources, a 401 error is generated. The following uri is self link