Schilit, B. N., Golovchinsky, G., & Price, M. N. (1998). Beyond paper: Supporting active reading with free form digital ink annotations. Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 249–256

https://doi.org/10.1145/274644.274680

An early Augmented reading system, XLibris, demonstrating pen-on-tablet ink annotation. A few non-imitative design elements:

• a compact representation of the page’s location in the book
• a page thumbnail view as we see in modern PDF viewers
• a “collapsed” representation of the text showing only the portions of the document around annotations, called “The Reader’s Notebook”
  • very much like a prototype I designed earlier this year! oops!
• the system attempts to find papers related to annotations and displays links to them in the margin