This book compiles the correspondence between Vicente-Juan Ballester Olmos and Eduardo Buelta, pioneer of ufology in Spain and one of the first in the world to suggest a correlation between UFO waves and the opposition phase of planet Mars

This is the third volume in a series of correspondence compilations with early Spanish ufologists, following the previous ones (with Antonio Ribera and with José-Tomas Ramirez y Barberò).

The book (138 pages in large format, in Spanish) is also including all Buelta’s historical articles published in the CEI Bulletin (journal of the Centro de Estudios Interplanetarios, in Barcelona). It can be ordered from UPIAR Store.