To avoid hijacking a request this post is a response to what seems to be a divergens in opinions about when it's allowed to post links as response to a request.
Primarily this response
[Login to see the link]
Basically I don't think we disagree, but I think some clarification is needed.
Whenever a user post a link as response to a request, I expect that every attempt possible has been made to verify that the content is what the OP has asked for.
If a link is found on the net it is not possible for all users to check the content of each file. You have to rely on the source for verification. No user subscribes to more hosts than necessary to meet their own demands.
Several requests has been solved by a users posting premium links. This allows other users to transfer the files to a source allowing free download.
Regarding the specific link supplied by [Login to see the link] , he has checked the ISBN 10. The ISBN is unique for each printed book. No other book has the same ISBN.
Besides that he also specified that the link was premium, and that he doesn't subscribe to the host.
As the file does not fulfill the request, the post does not count as useful help (request / help balance).
No need for you to stop trying to help. On the other hand if it's your second attempt using the specific source, it looks like the source is not reliable.
I do hope you will not give up and that you will continue to try to help solve more requests in the future.