Here is a collection of online books that might prove useful to your health professional students that are volunteering over the class break. I learned of them on the hif-net-at-WHO discussion list.
HealthWrights-Workgroup for people's health and rights books online
http://www.healthwrights.org/booksonline.htm

Your students could leave this link with their host clinics/organizations, and point out the additional resources that are available in each of the titles, such as the link to Addresses for Teaching Materials included in "When There is No Doctor" - http://www.healthwrights.org/books/WTINDonline.htm