French.
SEIS was produced by the French Space Agency (CNES), with the participation of the Institut de Physique du Globe de Paris (IPGP), the Swiss Federal Institute of Technology (ETH), the Max Planck Institute for Solar System Research (MPS), Imperial College, Institut supérieur de l'aéronautique et de l'espace (ISAE) and JPL
https://en.wikipedia.org/wiki/Seismi...rior_Structure