From Viking Direct:

Inspired in anticipation of a return to Westeros for the final season of the massively popular series (and because we know the night is dark and full of terrors…), office supplies maker Viking Direct worked with artist Andy Singleton to create a massive 13-metre-long dragon made of 1,200 sheets of A4 paper, which took 100 studio hours to design and create. A further 10 hours were then needed to install the creation in the Viking office.