Potamon fluviatile as well as on the island of Sicily. Although it used to be found as far north as Lake Garda, "P. fluviatile" no longer occurs north of the River Po. In 1997 a population of "P. fluviatile" was discovered under the ruins of Trajan's Forum in the heart of Rome, living in canals built by the Etruscans which connect to the "Cloaca Maxima". Based on a genetic analysis, which demonstrated that these crabs were similar to those in Greece, researchers believe that they had been brought by the Greeks before the founding of the city, some 3000 years ago. The
If This Is a Man not merely its lexical but also its inner faithfulness." Robert S. C. Gordon writes that Levi went on to develop a close relationship with Reidt. The German edition contains a special preface addressed to the German people, which Levi said he wrote out of passionate necessity to remind them what they had done. "If This Is a Man" is often published alongside Levi's second work of witness, "The Truce" (Italian title: "La Tregua"). The book is introduced by a poem. The construction "If .." invites the reader to make a judgment. It alludes to the treatment of people as "Untermenschen"