Hagfors, T. MPI for Aeronomy, Max Planck Institute for Solar System Research, Max Planck Society;
Hagfors, T. (1998). Ground penetrating radar for planetary exploration. In E., Attema, G., Schwehm, & A., Wilson (Eds.), Remote Sensing Methodology for Earth Observation and Planetary Exploration (pp. 147-156). Noordwijk: ESA Publ. Div.