Increasing the resilience of communities through volunteering : lessons learned from the IVCO conference in 2016 that can help national and international volunteers achieve impact in fragile contexts and contribute to the 2030 agenda for sustainable development, from a GIZ perspective / giz, Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH ; author: Susann Tischendorf, GIZ, Bonn, Germany ; responsible: Suzanne Gentges, GIZ, Bonn, Germany ; editor: Darcy Gallucio, Washington, D.C., USA