English: Area of demographic collapse following the Ilopango eruption. based on file: Central american mountains.jpg and Figure 10.7 page 251 from "Eruptions that Shook the World" by Clive Oppenheimer, Cambridge University Press, 2011
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.