Jean Barbier released a book of scales and arpeggios with variations called "Technique Rationnelle du Violoncelle". Although this book never became a staple to the cello literature, it has some very interesting interpretations and exercises that a cellist will find quite appealing. This is a reprint of the only known edition (permanently out-of-print) by Max Eschig, 1935. Plate M.E.4205, in Paris. A worthwhile investment for the price to do some in-depth...