The 45 works Jan Kleefstra wrote during Henry Mentink's walking tour with a wheelbarrow full of earth, from the Netherlands to UNESCO in Paris, with the request to put the Earth on the World Heritage List, appears in book form. The works are written in Dutch, the book is called 'Een kruitocht over Aarde', it was designed by Rutger Zuyderveldt and it is published by The Optimist. You can order it here.