GVP is using GeoServer software to provide WFS webservices; other data-retrieval options such as Web Coverage Service (WCS) and Web Map Service (WMS) are not available. However, the WFS options do allow retrieval using CSV, GML, GeoJSON, KML, and Shapefile formats.
These layers contain limited data used by the "Eruptions, Earthquakes, & Emissions" web application.
Global Volcanism Program, 2013. Volcanoes of the World, v. 4.10.1. Venzke, E (ed.). Smithsonian Institution. Downloaded 25 Jul 2021. https://doi.org/10.5479/si.GVP.VOTW4-2013