Which Is More Effective for Learning German and Japanese Language, Paper or Digital?

Recently, many people often say how practical is the digital media. Moreover, there are many researches on this topic that compare the use of paper and the digital media, but unfortunately, only the moment in which the user is actually using one of these two media is taken into account. We researched a group of Japanese and German subjects about their ability to remember some words on the next day, three days later and a week after they first tried to memorize them. The results demonstrated that users who want to learn in a short term should use digital media, only if they have a lot of experience using digital media in general. But if the user wants to learn something in a long term, might prefer to use Paper.