It is published by Loyola Press
http://www.loyolapress.com/exercises-in-english-2008-store.htm
It is a very well designed , very easy to use curriculum. Loyola press is a Catholic Publisher, however this series is completly secular.
It is exactly the same as Voyages in English
http://www.welltrainedmind.com/O00VIE.html
Hope this helps