Here is the Google translation of the blurb:
A name, emblem, a man, a myth. This could be summed up very existence of Magma. A name that reflects the lashes and intense bubbling behind the group's existence, an emblem, as a standard, alone represents the strength and all the surrounding cosmology, a myth, that of a people with his fears, his doubts, his struggles and his tongue, so dark and clear at once a man at last as the history of Magma seems to be confused with that from the beginning, is, if not the sole creator of 'work, the steadfast stand of the group: Christian Vander.
For forty years, Magma through the French musical landscape outside the fads and trends. Called Zeuhl, this crossing of choral music, avant-garde rock and jazz, innovates through lyrics sung in an imaginary language sounding Germanic and Slavic, Kobaïen. Influenced by the charismatic personality of its composer, singer and drummer, Christian Vander, Magma has built around his music an entire universe centered on a spiritual quest through the myths and legends of Magma, the dream world.
Philippe Gonin invites us to this book to decipher the myths and analyze the functioning of various formations of Magma. Especially the music he likes, explaining, album after album, song after song, how a work is constructed and operates.