I am not sure exactly what you are asking, but....
You have two way of adding supporting information into you database.
1) As media. This can be in the form of a picture, video, PDF, electronic document etc
2) As imbedded words, typed out using the source text field
You can also keep hyperlinks in your NOTEs and IIRC can use a FMT field to store the links as well.
However, I do not stop with keeping everything in the database. I always keep paper and electronic copies of the information in a file cabinet in my personal library. Fires happen, business fail, hyperlinks can change, governments can change, so I never depend on others to maintain copies of my found data. My personal library becomes a permanent backup of the database.