Sometimes they scan it. Sometimes they already have it in a PDF. Sometimes they extract it from a larger PDF. There are many ways they get it in digital form and then upload it onto learning management systems.
To be clear, the study that we did at York University did not have anything to to with links, so any links were excluded. It was just documents that were posted on the learning management systems, and, importantly, in that study we needed to see whether or not they already had the rights for those works, because you have heard of hundreds of millions of dollars being spent on accessing content, and those claims were made to the judge as well. York said at the beginning of the process that most of what they copy they have licences for.
By the end of the hearing, they had to abandon that claim completely because they could not marry the works they upload on learning management systems and copy in course packs with the licences that they have. It is not a question of faulty paperwork. It's because these are different works.