Mascagni, P. L'amico Fritz, c1891 t.p. (E. Suardon)
Mascagni, P. L'amico Fritz [SR] p2000 container (P. Suardon (N(icola) Daspuro)) insert (P. Suardon is an anagrammatic pseudonym)
Italian Wikipedia, June 30, 2016 (Nicola Daspuro; born January 19, 1853, Lecce, died December 13, 1941, Naples; Italian writer, journalist, and librettist; he signed L'amico Fritz and other works under the pseudonym P. Suardon)