N. GuimarĂ£esT. ChambelJ. Bidarra2010-05-212014-11-142010-05-212014-11-1420002000http://hdl.handle.net/10451/14341http://repositorio.ul.pt/handle/10455/5970engComputer ScienceFrom Cognitive Maps to Hypervideo: Supporting Flexible and Rich Learner-Centred Environmentsjournal article