The seventeenth issue of the collection of Greeting Cards op. 170 is the Ricercare sul nome di Luigi Dallapiccola, another of the dearest friends and colleagues of Castelnuovo-Tedesco, with whom, even at a great distance, the human and spiritual correspondence was interrupted only by the death of Mario. "Gigino," defined "my old friend, and musician for whom I have the highest consideration," was the dedicatee of this work, of which the author was proud as the best of all his "Pezzi Alfabetici" and which was printed by the Florentine publisher Forlivesi in 1959. Preceded by the illustration of two musical transpositions of the letters of the alphabet (one with chromatically ascending notes, the other descending) and identified the corresponding "musical mottos" forming the name and surname of the dedicatee, Castelnuovo-Tedesco builds a Prelude, a Fanfare and a monumental Fugue on these melodic cells, creating a contrapuntal structure of great complexity and expressive variety, as well as of considerable instrumental commitment.