"Religious Conversion: a Biopsychological Study" merits the attention of anyone interested in the question of religion and early XXth century psychology or psychoanalysis (Freud himself refers to de Sanctis' book in his 1928 article entitled "A Religious Experience").

This edition, while practically the photocopy of a student's book (expect underlined passages and handwritten annotations in the margins), is despite all almost good enough to work with. The only serious issue about it is the missing pages (142 and 143 do not appear in my copy). This is quite frustrating, but it may be better than paying 100 € for an old edition...